Add solution for Challenge 1 by zylbeyondlimits #912
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WalkthroughAdds new Go solution files across multiple challenges (1, 2, 3, 6, 18, 21, 22) plus a Gin-based HTTP CRUD solution; each file introduces small, self-contained functions/types and a CLI or HTTP demo where applicable. Changes
Estimated code review effort🎯 4 (Complex) | ⏱️ ~45 minutes
Possibly related PRs
Pre-merge checks❌ Failed checks (2 warnings, 1 inconclusive)
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Actionable comments posted: 1
🧹 Nitpick comments (1)
challenge-1/submissions/zylbeyondlimits/solution-template.go (1)
10-10: Consider more flexible input parsing.The format string
"%d, %d"requires an exact match with comma and space. If users input"1,2"or"1 2", parsing will fail. For a more robust solution, you might consider usingbufio.Scannerwithstrings.Splitto handle various formats.🔎 Alternative approach for flexible parsing
import ( + "bufio" "fmt" + "os" + "strconv" + "strings" ) func main() { - var a, b int - // Read two integers from standard input - _, err := fmt.Scanf("%d, %d", &a, &b) + scanner := bufio.NewScanner(os.Stdin) + scanner.Scan() + parts := strings.Split(scanner.Text(), ",") if err != nil { - fmt.Println("Error reading input:", err) + fmt.Println("Error reading input:", scanner.Err()) return } + if len(parts) != 2 { + fmt.Println("Expected two comma-separated integers") + return + } + a, err := strconv.Atoi(strings.TrimSpace(parts[0])) + if err != nil { + fmt.Println("Error parsing first integer:", err) + return + } + b, err := strconv.Atoi(strings.TrimSpace(parts[1])) + if err != nil { + fmt.Println("Error parsing second integer:", err) + return + } // Call the Sum function and print the result result := Sum(a, b) fmt.Println(result) }
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challenge-1/submissions/zylbeyondlimits/solution-template.go(1 hunks)
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challenge-1/submissions/zylbeyondlimits/solution-template.go (1)
7-25: LGTM! Core implementation is correct.The solution correctly reads two integers, computes their sum, and outputs the result. The logic is sound and appropriate for Challenge 1.
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| // Sum returns the sum of a and b. | ||
| func Sum(a int, b int) int { | ||
| // TODO: Implement the function |
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Remove the stale TODO comment.
The Sum function is already implemented on line 24. The TODO comment is misleading and should be removed to avoid confusion about whether additional work is required.
🔎 Proposed fix
// Sum returns the sum of a and b.
func Sum(a int, b int) int {
- // TODO: Implement the function
return a + b
}📝 Committable suggestion
‼️ IMPORTANT
Carefully review the code before committing. Ensure that it accurately replaces the highlighted code, contains no missing lines, and has no issues with indentation. Thoroughly test & benchmark the code to ensure it meets the requirements.
| // TODO: Implement the function | |
| // Sum returns the sum of a and b. | |
| func Sum(a int, b int) int { | |
| return a + b | |
| } |
🤖 Prompt for AI Agents
In challenge-1/submissions/zylbeyondlimits/solution-template.go around line 23,
the stale "// TODO: Implement the function" comment sits directly above the
implemented Sum function and is misleading; remove that TODO comment line so the
source reflects the completed implementation and commit the change.
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Actionable comments posted: 0
🧹 Nitpick comments (2)
challenge-2/submissions/zylbeyondlimits/solution-template.go (2)
9-21: LGTM! Main function correctly implements the challenge flow.The input reading, function call, and output logic are all correct. The program cleanly handles the standard case where input is available.
Optional: Consider adding error handling for robustness
If you want to handle I/O errors explicitly, you could add an error check:
func main() { // Read input from standard input scanner := bufio.NewScanner(os.Stdin) if scanner.Scan() { input := scanner.Text() // Call the ReverseString function output := ReverseString(input) // Print the result fmt.Println(output) } + if err := scanner.Err(); err != nil { + fmt.Fprintf(os.Stderr, "Error reading input: %v\n", err) + } }
23-32: Excellent algorithm! The rune-based reversal correctly handles Unicode characters.The two-pointer swap approach is efficient and the use of runes ensures proper handling of multi-byte UTF-8 characters.
Consider translating inline comments to English for broader accessibility.
The comments on lines 26 and 28 are in Chinese, which may limit readability for international contributors.
Suggested translation
func ReverseString(s string) string { runes := []rune(s) - // 只需要循环到长度的一半 + // Only need to loop to half the length for i, j := 0, len(runes)-1; i < j; i, j = i+1, j-1 { - // Go 独有的简便交换写法 + // Go's convenient tuple swap syntax runes[i], runes[j] = runes[j], runes[i] } return string(runes) }
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Actionable comments posted: 0
🧹 Nitpick comments (4)
challenge-3/submissions/zylbeyondlimits/solution-template.go (4)
16-20: Remove TODO comment and consider duplicate ID validation.The method is fully implemented, so the TODO comment on line 18 should be removed. Additionally, consider validating that an employee with the same ID doesn't already exist before adding.
🔎 Proposed improvements
// AddEmployee adds a new employee to the manager's list. func (m *Manager) AddEmployee(e Employee) { - // TODO: Implement this method + // Check for duplicate ID (optional enhancement) + for _, existing := range m.Employees { + if existing.ID == e.ID { + return // or handle error + } + } m.Employees = append(m.Employees, e) }
22-31: Consider using English for code comments.The method implementation is correct, but the Chinese comments on lines 22 and 26 may reduce maintainability for contributors who don't read Chinese. Consider translating them to English for broader accessibility.
🔎 Suggested translation
-// RemoveEmployee 推荐做法：原地删除 +// RemoveEmployee removes an employee by ID using in-place deletion func (m *Manager) RemoveEmployee(id int) { for i, e := range m.Employees { if e.ID == id { - // 使用切片拼接实现原地删除，无需申请 newEmployees 内存 + // Use slice reslicing for in-place deletion without allocating new memory m.Employees = append(m.Employees[:i], m.Employees[i+1:]...) - return // 找到并删除后直接返回 + return // Return immediately after deletion } } }
33-44: Remove TODO and consider conventional range syntax.The method is correctly implemented. Two minor style points:
- Line 35: Remove the TODO comment since the method is complete.
- Line 40: The parentheses around
m.Employeesin the range clause are valid but unconventional. Standard Go style omits them.🔎 Proposed style improvements
// GetAverageSalary calculates the average salary of all employees. func (m *Manager) GetAverageSalary() float64 { - // TODO: Implement this method if len(m.Employees) == 0 { return 0 } sum := 0.0 - for _, employee := range(m.Employees) { + for _, employee := range m.Employees { sum = sum + employee.Salary } return sum / float64(len(m.Employees)) }
46-54: Translate comment to English for consistency.The implementation is excellent and correctly returns a pointer to the slice element to avoid copying. However, the Chinese comment on line 46 should be translated to English for better maintainability.
🔎 Suggested translation
-// FindEmployeeByID 返回真实的内存地址 +// FindEmployeeByID returns a pointer to the employee with the given ID, or nil if not found func (m *Manager) FindEmployeeByID(id int) *Employee { for i := range m.Employees { if m.Employees[i].ID == id { - return &m.Employees[i] // 返回切片中元素的真实地址 + return &m.Employees[i] // Return address of the actual slice element } } return nil }
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challenge-3/submissions/zylbeyondlimits/solution-template.go(1 hunks)
🔇 Additional comments (2)
challenge-3/submissions/zylbeyondlimits/solution-template.go (2)
5-14: LGTM!The struct definitions are clean and appropriate for the employee management system.
56-68: LGTM!The
mainfunction effectively demonstrates all the Manager methods with proper nil checking and clear output formatting.
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Actionable comments posted: 0
🧹 Nitpick comments (3)
challenge-6/submissions/zylbeyondlimits/solution-template.go (3)
9-11: Use English comments and verify apostrophe handling requirements.The comments are in Chinese, which reduces maintainability in an English-language open-source repository. Consider translating them to English for better collaboration.
Additionally, removing all apostrophes transforms words like "it's" → "its" and "don't" → "dont", which may change their semantic meaning. Please verify that this approach aligns with the challenge requirements.
🔎 Suggested English translation
- // 1. 特殊处理：去掉撇号（'），将 "Let's" 变成 "Lets" - // 必须在正则拆分前完成这一步，否则 "Let's" 会被拆成 "Let" 和 "s" + // 1. Special handling: Remove apostrophes (') to convert "Let's" to "Lets" + // This must be done before regex splitting, otherwise "Let's" would be split into "Let" and "s" cleanedText := strings.ReplaceAll(text, "'", "")
13-18: Translate comments to English and verify Unicode requirements.The comments are in Chinese, which should be translated to English for consistency and maintainability.
The regex pattern
[a-zA-Z0-9]+only matches ASCII alphanumeric characters. This excludes words with accented characters (e.g., "café", "naïve") or non-Latin scripts. Please verify whether the challenge requires ASCII-only word matching or should handle international text.🔎 Suggested English translation
- // 2. 正则查找：只匹配连续的字母或数字 - // 这一步隐式地解决了分隔符问题： - // - "new-lines" 中的 "-" 不匹配，所以会被拆分为 "new" 和 "lines" - // - "dog." 中的 "." 不匹配，所以被丢弃 + // 2. Regex matching: Only match consecutive letters or numbers + // This step implicitly handles separators: + // - The "-" in "new-lines" doesn't match, so it splits into "new" and "lines" + // - The "." in "dog." doesn't match, so it's discarded re := regexp.MustCompile(`[a-zA-Z0-9]+`) words := re.FindAllString(cleanedText, -1)
20-24: Good use of map pre-allocation; translate comment to English.The pre-allocation of the map with a capacity hint is a good performance optimization. The logic for converting words to lowercase and counting frequencies is correct.
However, the comment on line 22 is in Chinese and should be translated to English for consistency.
🔎 Suggested English translation
wordMap := make(map[string]int, len(words)) for _, word := range words { - // 3. 转小写并统计 + // 3. Convert to lowercase and count wordMap[strings.ToLower(word)]++ }
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Actionable comments posted: 0
🧹 Nitpick comments (1)
challenge-18/submissions/zylbeyondlimits/solution-template.go (1)
19-26: LGTM! Correct formula and proper floating-point handling.The conversion formula is accurate, and using
9.0/5.0correctly avoids integer division. The rounding to 2 decimals ensures consistent precision.Optional: Consider translating the Chinese comments (lines 22-23) to English for consistency with the rest of the codebase.
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challenge-18/submissions/zylbeyondlimits/solution-template.go(1 hunks)
🔇 Additional comments (3)
challenge-18/submissions/zylbeyondlimits/solution-template.go (3)
8-17: LGTM!The example usage clearly demonstrates both temperature conversions with appropriate formatting.
28-34: LGTM! Correct inverse conversion.The formula is accurate and properly uses floating-point literals. The implementation mirrors the forward conversion appropriately.
36-40: LGTM! Clean rounding implementation.The rounding logic using
math.Pow10andmath.Roundis correct and provides flexible decimal precision control.
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Actionable comments posted: 0
🧹 Nitpick comments (1)
challenge-21/submissions/zylbeyondlimits/solution-template.go (1)
7-24: Consider adding edge case tests.The main function demonstrates the basic functionality well, but adding tests for edge cases would make the solution more robust and comprehensive. Consider testing:
- Target not found in array (e.g., target = 20)
- Empty array
- Single-element array
- Target at array boundaries (first/last element)
🔎 Example expanded test cases
func main() { // Example sorted array for testing arr := []int{1, 3, 5, 7, 9, 11, 13, 15, 17, 19} // Test binary search target := 7 index := BinarySearch(arr, target) fmt.Printf("BinarySearch: %d found at index %d\n", target, index) // Test recursive binary search recursiveIndex := BinarySearchRecursive(arr, target, 0, len(arr)-1) fmt.Printf("BinarySearchRecursive: %d found at index %d\n", target, recursiveIndex) // Test find insert position insertTarget := 8 insertPos := FindInsertPosition(arr, insertTarget) fmt.Printf("FindInsertPosition: %d should be inserted at index %d\n", insertTarget, insertPos) + + // Test target not found + notFound := BinarySearch(arr, 20) + fmt.Printf("BinarySearch: 20 not found, result: %d\n", notFound) + + // Test empty array + emptyArr := []int{} + emptyResult := BinarySearch(emptyArr, 5) + fmt.Printf("BinarySearch on empty array: %d\n", emptyResult) + + // Test boundary elements + firstElement := BinarySearch(arr, 1) + lastElement := BinarySearch(arr, 19) + fmt.Printf("BinarySearch: first element at %d, last element at %d\n", firstElement, lastElement) }
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challenge-21/submissions/zylbeyondlimits/solution-template.go(1 hunks)
🔇 Additional comments (3)
challenge-21/submissions/zylbeyondlimits/solution-template.go (3)
28-46: Well-implemented iterative binary search!The implementation is clean and correct. The overflow-safe mid calculation (
mid := left + (right-left)/2) is particularly noteworthy, as it prevents potential integer overflow issues that could occur with the naive(left + right) / 2approach.
48-69: Solid recursive implementation.The recursive binary search is correctly implemented with proper base case handling and overflow-safe mid calculation. The logic is clean and easy to follow.
71-92: Correct insertion position logic.The implementation correctly identifies where to insert a target value to maintain sorted order. The overflow-safe mid calculation is consistently applied.
The behavior when the target already exists (returning its current position) is documented in the comment, which is a valid design choice for this use case.
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Actionable comments posted: 8
🧹 Nitpick comments (3)
challenge-22/submissions/zylbeyondlimits/solution-template.go (3)
29-31: Remove commented-out test code.Commented-out code adds clutter and is better tracked through version control.
🔎 Proposed cleanup
- // 测试无法凑出的情况 (例如没有1分硬币，只要凑3分) - // unmatchableCoins := MinCoins(3, []int{2, 5}) - // fmt.Printf("Test Unmatchable (3 with [2,5]): %d\n", unmatchableCoins)
36-63: Add input validation for edge cases.The function doesn't validate inputs, which could lead to panics or incorrect results for edge cases such as negative amounts, empty or nil denomination slices, or zero amounts.
🔎 Proposed input validation
func MinCoins(amount int, denominations []int) int { + // Validate inputs + if amount < 0 { + return -1 + } + if amount == 0 { + return 0 + } + if len(denominations) == 0 { + return -1 + } + count := 0 remaining := amount
40-42: Document or validate the sorted denominations assumption.The algorithm assumes
denominationsis sorted in ascending order (line 9 comment references this requirement). If unsorted denominations are passed, the greedy approach will fail. Consider either validating the sort order or prominently documenting this precondition in the function godoc.🔎 Option 1: Add validation
func MinCoins(amount int, denominations []int) int { + // Validate denominations are sorted + for i := 1; i < len(denominations); i++ { + if denominations[i] < denominations[i-1] { + return -1 // or panic with descriptive error + } + } + count := 0 remaining := amountOption 2: Document the precondition clearly
-// MinCoins returns the minimum number of coins needed to make the given amount. -// If the amount cannot be made with the given denominations, return -1. +// MinCoins returns the minimum number of coins needed to make the given amount +// using a greedy algorithm. +// +// Precondition: denominations must be sorted in ascending order. +// If the amount cannot be made with the given denominations, returns -1. func MinCoins(amount int, denominations []int) int {
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challenge-22/submissions/zylbeyondlimits/solution-template.go(1 hunks)packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go(1 hunks)
🔇 Additional comments (4)
packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go (4)
1-27: Good basic structure with standard types.The User struct correctly uses Gin's binding tags for validation, and the Response struct provides a standardized API response format.
50-57: LGTM with mutex protection pending.The handler correctly returns all users. Once the concurrency fix is applied (protecting the
usersslice with a mutex), this will be safe.
170-199: Good search implementation with proper validation.The function correctly validates the required query parameter and implements case-insensitive substring matching. The Chinese comments should be translated (covered in previous comment).
59-80: Inconsistent error details in ID parsing responses across handlers.Line 63 includes
err.Error()when ID parsing fails (good practice), but you should verify that lines 111 and 150 in updateUser and deleteUser handlers follow the same pattern for consistency. If they omit error details, align all handlers to either include or exclude error information uniformly.
| func MinCoins(amount int, denominations []int) int { | ||
| count := 0 | ||
| remaining := amount | ||
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| // 贪心算法：从最大面额（切片末尾）开始向前遍历 | ||
| for i := len(denominations) - 1; i >= 0; i-- { | ||
| coin := denominations[i] | ||
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| // 只要剩余金额大于等于当前硬币面额 | ||
| if remaining >= coin { | ||
| // 使用除法计算当前面额需要几枚 | ||
| num := remaining / coin | ||
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| // 累加硬币数量 | ||
| count += num | ||
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| // 更新剩余金额 (取余数) | ||
| remaining %= coin | ||
| } | ||
| } | ||
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| // 题目要求：如果无法凑出该金额，返回 -1 | ||
| if remaining != 0 { | ||
| return -1 | ||
| } | ||
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| return count | ||
| } |
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Greedy algorithm doesn't guarantee optimal solution for arbitrary denominations.
The greedy approach (largest coin first) works for US coin denominations but fails for arbitrary denomination sets. For example, with denominations [1, 3, 4] and amount 6, greedy produces 3 coins [4, 1, 1], but the optimal solution is 2 coins [3, 3].
If the challenge accepts arbitrary denominations, consider implementing dynamic programming for correctness.
💡 Dynamic programming approach (if arbitrary denominations are supported)
func MinCoins(amount int, denominations []int) int {
if amount == 0 {
return 0
}
if len(denominations) == 0 {
return -1
}
// dp[i] represents minimum coins needed for amount i
dp := make([]int, amount+1)
for i := 1; i <= amount; i++ {
dp[i] = amount + 1 // Initialize with impossible value
}
dp[0] = 0
for i := 1; i <= amount; i++ {
for _, coin := range denominations {
if coin <= i {
dp[i] = min(dp[i], dp[i-coin]+1)
}
}
}
if dp[amount] > amount {
return -1
}
return dp[amount]
}
func min(a, b int) int {
if a < b {
return a
}
return b
}🤖 Prompt for AI Agents
In challenge-22/submissions/zylbeyondlimits/solution-template.go around lines 36
to 63 the current Greedy implementation (largest-coin-first) is incorrect for
arbitrary denomination sets; replace it with a dynamic programming solution:
handle amount==0 and empty denominations early, allocate dp slice of size
amount+1 with dp[0]=0 and dp[i]=amount+1 for i>0, iterate i from 1..amount and
for each coin in denominations if coin<=i set dp[i]=min(dp[i], dp[i-coin]+1),
and finally return -1 if dp[amount]>amount else dp[amount]; remove the greedy
logic and ensure a small helper min function or inline comparison is used.
| func CoinCombination(amount int, denominations []int) map[int]int { | ||
| // 初始化 map | ||
| sol := make(map[int]int) | ||
| remaining := amount | ||
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| // 贪心算法：从最大面额开始 | ||
| for i := len(denominations) - 1; i >= 0; i-- { | ||
| coin := denominations[i] | ||
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| if remaining >= coin { | ||
| num := remaining / coin | ||
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| if num > 0 { | ||
| sol[coin] = num | ||
| remaining %= coin | ||
| } | ||
| } | ||
| } | ||
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| // 题目要求：如果无法凑出，返回空 map | ||
| if remaining != 0 { | ||
| return map[int]int{} | ||
| } | ||
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| return sol | ||
| } No newline at end of file |
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🛠️ Refactor suggestion | 🟠 Major
Significant code duplication with MinCoins.
Both MinCoins and CoinCombination implement nearly identical greedy logic. This violates the DRY principle and increases maintenance burden.
🔎 Proposed refactoring to eliminate duplication
+// coinChangeGreedy is the shared greedy implementation
+func coinChangeGreedy(amount int, denominations []int) (count int, breakdown map[int]int, ok bool) {
+ breakdown = make(map[int]int)
+ remaining := amount
+
+ for i := len(denominations) - 1; i >= 0; i-- {
+ coin := denominations[i]
+
+ if remaining >= coin {
+ num := remaining / coin
+ count += num
+ if num > 0 {
+ breakdown[coin] = num
+ }
+ remaining %= coin
+ }
+ }
+
+ if remaining != 0 {
+ return 0, map[int]int{}, false
+ }
+ return count, breakdown, true
+}
+
func MinCoins(amount int, denominations []int) int {
- count := 0
- remaining := amount
-
- // 贪心算法：从最大面额（切片末尾）开始向前遍历
- for i := len(denominations) - 1; i >= 0; i-- {
- coin := denominations[i]
-
- // 只要剩余金额大于等于当前硬币面额
- if remaining >= coin {
- // 使用除法计算当前面额需要几枚
- num := remaining / coin
-
- // 累加硬币数量
- count += num
-
- // 更新剩余金额 (取余数)
- remaining %= coin
- }
- }
-
- // 题目要求：如果无法凑出该金额，返回 -1
- if remaining != 0 {
+ count, _, ok := coinChangeGreedy(amount, denominations)
+ if !ok {
return -1
}
-
return count
}
func CoinCombination(amount int, denominations []int) map[int]int {
- // 初始化 map
- sol := make(map[int]int)
- remaining := amount
-
- // 贪心算法：从最大面额开始
- for i := len(denominations) - 1; i >= 0; i-- {
- coin := denominations[i]
-
- if remaining >= coin {
- num := remaining / coin
-
- if num > 0 {
- sol[coin] = num
- remaining %= coin
- }
- }
- }
-
- // 题目要求：如果无法凑出，返回空 map
- if remaining != 0 {
+ _, breakdown, ok := coinChangeGreedy(amount, denominations)
+ if !ok {
return map[int]int{}
}
-
- return sol
+ return breakdown
}Committable suggestion skipped: line range outside the PR's diff.
🤖 Prompt for AI Agents
In challenge-22/submissions/zylbeyondlimits/solution-template.go around lines 68
to 93, CoinCombination duplicates the greedy coin-selection logic used in
MinCoins; refactor by extracting the shared greedy algorithm into a single
helper (e.g., computeGreedyCombination(amount, denominations) (map[int]int, int)
or similar) that returns the coin counts and leftover, then call that helper
from both CoinCombination and MinCoins, keeping identical behavior (return empty
map when leftover != 0) and preserving input/output semantics.
| // In-memory storage | ||
| var users = []User{ | ||
| {ID: 1, Name: "John Doe", Email: "[email protected]", Age: 30}, | ||
| {ID: 2, Name: "Jane Smith", Email: "[email protected]", Age: 25}, | ||
| {ID: 3, Name: "Bob Wilson", Email: "[email protected]", Age: 35}, | ||
| } | ||
| var nextID = 4 |
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Critical: Data races on global state.
The global users slice and nextID counter are accessed concurrently by multiple HTTP handlers without synchronization. Gin processes requests in separate goroutines, leading to data races and potential crashes.
🔎 Proposed fix using sync.RWMutex
+import (
+ "sync"
+)
+
// In-memory storage
var users = []User{
{ID: 1, Name: "John Doe", Email: "[email protected]", Age: 30},
{ID: 2, Name: "Jane Smith", Email: "[email protected]", Age: 25},
{ID: 3, Name: "Bob Wilson", Email: "[email protected]", Age: 35},
}
var nextID = 4
+var usersMutex sync.RWMutexThen protect all reads with usersMutex.RLock()/usersMutex.RUnlock() and all writes with usersMutex.Lock()/usersMutex.Unlock() in each handler function.
Committable suggestion skipped: line range outside the PR's diff.
🤖 Prompt for AI Agents
In
packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go
around lines 29 to 35, the global users slice and nextID counter are unprotected
and cause data races under concurrent HTTP handlers; add a package-level
sync.RWMutex (e.g., usersMutex), and use usersMutex.RLock()/RUnlock() for all
read-only access to users and usersMutex.Lock()/Unlock() for any mutation
(adding, updating, deleting users) and for incrementing nextID (or use atomic
operations protected by the same mutex), ensuring every handler that reads or
writes users/nextID acquires the appropriate lock and releases it.
| func main() { | ||
| router := gin.Default() | ||
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| router.GET("/users", getAllUsers) | ||
| router.GET("/users/:id", getUserByID) | ||
| router.POST("/users", createUser) | ||
| router.PUT("/users/:id", updateUser) | ||
| router.DELETE("/users/:id", deleteUser) | ||
| router.GET("/users/search", searchUsers) | ||
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| router.Run(":8080") | ||
| } |
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Critical: Route registration order breaks /users/search endpoint.
Line 45 registers /users/search after /users/:id (line 41). Gin matches routes in order, so all requests to /users/search will be handled by getUserByID, treating "search" as an ID parameter. The search endpoint will never be reached.
🔎 Proposed fix: register search route first
func main() {
router := gin.Default()
router.GET("/users", getAllUsers)
+ router.GET("/users/search", searchUsers)
router.GET("/users/:id", getUserByID)
router.POST("/users", createUser)
router.PUT("/users/:id", updateUser)
router.DELETE("/users/:id", deleteUser)
- router.GET("/users/search", searchUsers)
router.Run(":8080")
}🤖 Prompt for AI Agents
In
packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go
around lines 37 to 48, the route for /users/search is registered after the
parameterized /users/:id route so requests to /users/search are captured by
getUserByID; move the router.GET("/users/search", searchUsers) registration
above the router.GET("/users/:id", getUserByID) registration so the static
search route is matched first and the search handler is reached.
| // 【重构】使用 findUserByID | ||
| user, _ := findUserByID(userID) |
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Minor: Use English for code comments.
Chinese comments (【重构】使用 findUserByID) should be translated to English for better collaboration in international projects.
🔎 Suggested translation
- // 【重构】使用 findUserByID
+ // Refactored: use findUserByID helper
user, _ := findUserByID(userID)Apply similar translations at lines 115, 128, 134, 154, 170, 174, 187.
Also applies to: 115-116, 154-155
🤖 Prompt for AI Agents
In
packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go
around lines 67-68 (and also update comments at 115-116, 128, 134, 154-155, 170,
174, 187), replace the Chinese inline comments (e.g. "【重构】使用 findUserByID") with
clear English equivalents (e.g. "Refactor: use findUserByID") so all code
comments are in English; keep the original intent and placement of each comment,
use consistent phrasing and punctuation, and run gofmt/organize imports if
needed after editing.
| // 【重构】使用 findUserByID | ||
| _, index := findUserByID(userID) | ||
| if index == -1 { | ||
| c.JSON(http.StatusNotFound, Response{Success: false, Message: "User updated unsuccessfully", Error: "User not found", Code: 404}) |
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Minor: Improve error message phrasing.
"User updated unsuccessfully" and "User deletion unsuccessfully" are awkwardly phrased. Consider using "Failed to update user" and "Failed to delete user" instead.
🔎 Proposed improvement
- c.JSON(http.StatusNotFound, Response{Success: false, Message: "User updated unsuccessfully", Error: "User not found", Code: 404})
+ c.JSON(http.StatusNotFound, Response{Success: false, Message: "Failed to update user", Error: "User not found", Code: 404})- c.JSON(http.StatusNotFound, Response{Success: false, Message: "User deletion unsuccessfully", Error: "User not found", Code: 404})
+ c.JSON(http.StatusNotFound, Response{Success: false, Message: "Failed to delete user", Error: "User not found", Code: 404})Also applies to: 157-157
🤖 Prompt for AI Agents
In
packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go
around lines 118 and 157, the error response messages use awkward phrasing
("User updated unsuccessfully" / "User deletion unsuccessfully"); update those
JSON response Message fields to use clearer wording such as "Failed to update
user" and "Failed to delete user" respectively, keeping the Error and Code
fields unchanged.
| // Helper function to find user by ID | ||
| func findUserByID(id int) (*User, int) { | ||
| for i := 0; i < len(users); i++ { | ||
| if users[i].ID == id { | ||
| return &users[i], i | ||
| } | ||
| } | ||
| return nil, -1 | ||
| } |
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Critical: Returning pointer to slice element is unsafe.
Line 205 returns &users[i], a pointer to an element in a slice. When the slice is modified by append (in createUser) or slice operations (in deleteUser), the underlying array may be reallocated, making all existing pointers invalid. This leads to use-after-free bugs and potential crashes.
🔎 Proposed fix: return by value or copy
Option 1: Return by value (recommended for this use case)
-func findUserByID(id int) (*User, int) {
+func findUserByID(id int) (User, int, bool) {
for i := 0; i < len(users); i++ {
if users[i].ID == id {
- return &users[i], i
+ return users[i], i, true
}
}
- return nil, -1
+ return User{}, -1, false
}Then update callers to check the bool instead of nil:
- user, _ := findUserByID(userID)
- if user == nil {
+ user, _, found := findUserByID(userID)
+ if !found {
c.JSON(http.StatusNotFound, Response{Success: false, Message: "User not found", Code: 404})
return
}
c.JSON(http.StatusOK, Response{
Success: true,
- Data: user,
+ Data: &user,
Message: "User found successfully",
Code: 200,
})Option 2: Use index-only lookups
Refactor to only return the index, and access users[index] at the call site while holding appropriate locks.
Committable suggestion skipped: line range outside the PR's diff.
🤖 Prompt for AI Agents
In
packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go
around lines 201 to 209, the helper findUserByID currently returns a pointer to
a slice element (&users[i]) which is unsafe because slice reallocation
(append/delete) can invalidate that pointer; change the function to return
either (a) the User by value and an index/ok flag (recommended) or (b) only the
index (int) and let callers access users[index] locally; then update all call
sites to stop checking for nil pointers and instead check the returned ok/index
and work with a value or direct indexed access to avoid holding pointers to the
slice backing array.
| func validateUser(user User) error { | ||
| if user.Name == "" { | ||
| return fmt.Errorf("name is required") | ||
| } | ||
| if user.Email == "" { | ||
| return fmt.Errorf("email is required") | ||
| } | ||
| // 简单的 Email 格式检查 | ||
| if !strings.Contains(user.Email, "@") { | ||
| return fmt.Errorf("invalid email format") | ||
| } | ||
| return nil | ||
| } No newline at end of file |
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Major: Email validation is too simplistic.
Line 220 only checks if the email contains "@", which accepts invalid formats like "@", "test@", "@domain.com", or "user@@example". This allows invalid data into the system.
🔎 Proposed improvement using regex
+import (
+ "regexp"
+)
+
+var emailRegex = regexp.MustCompile(`^[a-zA-Z0-9._%+-]+@[a-zA-Z0-9.-]+\.[a-zA-Z]{2,}$`)
+
func validateUser(user User) error {
if user.Name == "" {
return fmt.Errorf("name is required")
}
if user.Email == "" {
return fmt.Errorf("email is required")
}
- // 简单的 Email 格式检查
- if !strings.Contains(user.Email, "@") {
+ if !emailRegex.MatchString(user.Email) {
return fmt.Errorf("invalid email format")
}
return nil
}Alternatively, consider using a well-tested email validation library for production code.
Committable suggestion skipped: line range outside the PR's diff.
🤖 Prompt for AI Agents
In
packages/gin/challenge-1-basic-routing/submissions/zylbeyondlimits/solution.go
around lines 212 to 224, the email check only tests for "@" and accepts invalid
values; replace it with a proper regex-based validation (or call a vetted email
validation library) that ensures exactly one "@", non-empty local and domain
parts, no consecutive "@" and a valid domain (e.g., domain contains a dot and
valid characters); compile the regex once (or reuse the library) and return
fmt.Errorf("invalid email format") when the regex/library check fails.
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