Translate all code to English (#1836)

* Review the EN heading format.

* Fix pythontutor headings.

* Fix pythontutor headings.

* bug fixes

* Fix headings in **/summary.md

* Revisit the CN-to-EN translation for Python code using Claude-4.5

* Revisit the CN-to-EN translation for Java code using Claude-4.5

* Revisit the CN-to-EN translation for Cpp code using Claude-4.5.

* Fix the dictionary.

* Fix cpp code translation for the multipart strings.

* Translate Go code to English.

* Update workflows to test EN code.

* Add EN translation for C.

* Add EN translation for CSharp.

* Add EN translation for Swift.

* Trigger the CI check.

* Revert.

* Update en/hash_map.md

* Add the EN version of Dart code.

* Add the EN version of Kotlin code.

* Add missing code files.

* Add the EN version of JavaScript code.

* Add the EN version of TypeScript code.

* Fix the workflows.

* Add the EN version of Ruby code.

* Add the EN version of Rust code.

* Update the CI check for the English version  code.

* Update Python CI check.

* Fix cmakelists for en/C code.

* Fix Ruby comments

en/codes/go/chapter_sorting/bubble_sort.go

@@ -0,0 +1,38 @@
+// File: bubble_sort.go
+// Created Time: 2022-12-06
+// Author: Slone123c (274325721@qq.com)
+
+package chapter_sorting
+
+/* Bubble sort */
+func bubbleSort(nums []int) {
+	// Outer loop: unsorted range is [0, i]
+	for i := len(nums) - 1; i > 0; i-- {
+		// Inner loop: swap the largest element in the unsorted range [0, i] to the rightmost end of that range
+		for j := 0; j < i; j++ {
+			if nums[j] > nums[j+1] {
+				// Swap nums[j] and nums[j + 1]
+				nums[j], nums[j+1] = nums[j+1], nums[j]
+			}
+		}
+	}
+}
+
+/* Bubble sort (flag optimization) */
+func bubbleSortWithFlag(nums []int) {
+	// Outer loop: unsorted range is [0, i]
+	for i := len(nums) - 1; i > 0; i-- {
+		flag := false // Initialize flag
+		// Inner loop: swap the largest element in the unsorted range [0, i] to the rightmost end of that range
+		for j := 0; j < i; j++ {
+			if nums[j] > nums[j+1] {
+				// Swap nums[j] and nums[j + 1]
+				nums[j], nums[j+1] = nums[j+1], nums[j]
+				flag = true // Record element swap
+			}
+		}
+		if flag == false { // No elements were swapped in this round of "bubbling", exit directly
+			break
+		}
+	}
+}

en/codes/go/chapter_sorting/bubble_sort_test.go

@@ -0,0 +1,20 @@
+// File: bubble_sort_test.go
+// Created Time: 2022-12-06
+// Author: Slone123c (274325721@qq.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestBubbleSort(t *testing.T) {
+	nums := []int{4, 1, 3, 1, 5, 2}
+	bubbleSort(nums)
+	fmt.Println("After bubble sort completes, nums = ", nums)
+
+	nums1 := []int{4, 1, 3, 1, 5, 2}
+	bubbleSortWithFlag(nums1)
+	fmt.Println("After bubble sort completes, nums1 = ", nums1)
+}

en/codes/go/chapter_sorting/bucket_sort.go

@@ -0,0 +1,37 @@
+// File: bucket_sort.go
+// Created Time: 2023-03-27
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+import "sort"
+
+/* Bucket sort */
+func bucketSort(nums []float64) {
+	// Initialize k = n/2 buckets, expected to allocate 2 elements per bucket
+	k := len(nums) / 2
+	buckets := make([][]float64, k)
+	for i := 0; i < k; i++ {
+		buckets[i] = make([]float64, 0)
+	}
+	// 1. Distribute array elements into various buckets
+	for _, num := range nums {
+		// Input data range is [0, 1), use num * k to map to index range [0, k-1]
+		i := int(num * float64(k))
+		// Add num to bucket i
+		buckets[i] = append(buckets[i], num)
+	}
+	// 2. Sort each bucket
+	for i := 0; i < k; i++ {
+		// Use built-in slice sorting function, can also be replaced with other sorting algorithms
+		sort.Float64s(buckets[i])
+	}
+	// 3. Traverse buckets to merge results
+	i := 0
+	for _, bucket := range buckets {
+		for _, num := range bucket {
+			nums[i] = num
+			i++
+		}
+	}
+}

en/codes/go/chapter_sorting/bucket_sort_test.go

@@ -0,0 +1,17 @@
+// File: bucket_sort_test.go
+// Created Time: 2023-03-27
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestBucketSort(t *testing.T) {
+	// Assume input data is floating point, interval [0, 1)
+	nums := []float64{0.49, 0.96, 0.82, 0.09, 0.57, 0.43, 0.91, 0.75, 0.15, 0.37}
+	bucketSort(nums)
+	fmt.Println("After bucket sort completes, nums = ", nums)
+}

en/codes/go/chapter_sorting/counting_sort.go

@@ -0,0 +1,68 @@
+// File: counting_sort.go
+// Created Time: 2023-03-20
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+type CountingSort struct{}
+
+/* Counting sort */
+// Simple implementation, cannot be used for sorting objects
+func countingSortNaive(nums []int) {
+	// 1. Count the maximum element m in the array
+	m := 0
+	for _, num := range nums {
+		if num > m {
+			m = num
+		}
+	}
+	// 2. Count the occurrence of each number
+	// counter[num] represents the occurrence of num
+	counter := make([]int, m+1)
+	for _, num := range nums {
+		counter[num]++
+	}
+	// 3. Traverse counter, filling each element back into the original array nums
+	for i, num := 0, 0; num < m+1; num++ {
+		for j := 0; j < counter[num]; j++ {
+			nums[i] = num
+			i++
+		}
+	}
+}
+
+/* Counting sort */
+// Complete implementation, can sort objects and is a stable sort
+func countingSort(nums []int) {
+	// 1. Count the maximum element m in the array
+	m := 0
+	for _, num := range nums {
+		if num > m {
+			m = num
+		}
+	}
+	// 2. Count the occurrence of each number
+	// counter[num] represents the occurrence of num
+	counter := make([]int, m+1)
+	for _, num := range nums {
+		counter[num]++
+	}
+	// 3. Calculate the prefix sum of counter, converting "occurrence count" to "tail index"
+	// counter[num]-1 is the last index where num appears in res
+	for i := 0; i < m; i++ {
+		counter[i+1] += counter[i]
+	}
+	// 4. Traverse nums in reverse order, placing each element into the result array res
+	// Initialize the array res to record results
+	n := len(nums)
+	res := make([]int, n)
+	for i := n - 1; i >= 0; i-- {
+		num := nums[i]
+		// Place num at the corresponding index
+		res[counter[num]-1] = num
+		// Decrement the prefix sum by 1, getting the next index to place num
+		counter[num]--
+	}
+	// Use result array res to overwrite the original array nums
+	copy(nums, res)
+}

en/codes/go/chapter_sorting/counting_sort_test.go

@@ -0,0 +1,20 @@
+// File: counting_sort_test.go
+// Created Time: 2023-03-20
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestCountingSort(t *testing.T) {
+	nums := []int{1, 0, 1, 2, 0, 4, 0, 2, 2, 4}
+	countingSortNaive(nums)
+	fmt.Println("After counting sort (cannot sort objects) completes, nums = ", nums)
+
+	nums1 := []int{1, 0, 1, 2, 0, 4, 0, 2, 2, 4}
+	countingSort(nums1)
+	fmt.Println("After counting sort completes, nums1 = ", nums1)
+}

en/codes/go/chapter_sorting/heap_sort.go

@@ -0,0 +1,44 @@
+// File: heap_sort.go
+// Created Time: 2023-05-29
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+/* Heap length is n, start heapifying node i, from top to bottom */
+func siftDown(nums *[]int, n, i int) {
+	for true {
+		// If node i is largest or indices l, r are out of bounds, no need to continue heapify, break
+		l := 2*i + 1
+		r := 2*i + 2
+		ma := i
+		if l < n && (*nums)[l] > (*nums)[ma] {
+			ma = l
+		}
+		if r < n && (*nums)[r] > (*nums)[ma] {
+			ma = r
+		}
+		// Swap two nodes
+		if ma == i {
+			break
+		}
+		// Swap two nodes
+		(*nums)[i], (*nums)[ma] = (*nums)[ma], (*nums)[i]
+		// Loop downwards heapification
+		i = ma
+	}
+}
+
+/* Heap sort */
+func heapSort(nums *[]int) {
+	// Build heap operation: heapify all nodes except leaves
+	for i := len(*nums)/2 - 1; i >= 0; i-- {
+		siftDown(nums, len(*nums), i)
+	}
+	// Extract the largest element from the heap and repeat for n-1 rounds
+	for i := len(*nums) - 1; i > 0; i-- {
+		// Delete node
+		(*nums)[0], (*nums)[i] = (*nums)[i], (*nums)[0]
+		// Start heapifying the root node, from top to bottom
+		siftDown(nums, i, 0)
+	}
+}

en/codes/go/chapter_sorting/heap_sort_test.go

@@ -0,0 +1,16 @@
+// File: heap_sort_test.go
+// Created Time: 2023-05-29
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestHeapSort(t *testing.T) {
+	nums := []int{4, 1, 3, 1, 5, 2}
+	heapSort(&nums)
+	fmt.Println("After heap sort completes, nums = ", nums)
+}

en/codes/go/chapter_sorting/insertion_sort.go

@@ -0,0 +1,20 @@
+// File: insertion_sort.go
+// Created Time: 2022-12-12
+// Author: msk397 (machangxinq@gmail.com)
+
+package chapter_sorting
+
+/* Insertion sort */
+func insertionSort(nums []int) {
+	// Outer loop: sorted interval is [0, i-1]
+	for i := 1; i < len(nums); i++ {
+		base := nums[i]
+		j := i - 1
+		// Inner loop: insert base into the correct position within the sorted interval [0, i-1]
+		for j >= 0 && nums[j] > base {
+			nums[j+1] = nums[j] // Move nums[j] to the right by one position
+			j--
+		}
+		nums[j+1] = base // Assign base to the correct position
+	}
+}

en/codes/go/chapter_sorting/insertion_sort_test.go

@@ -0,0 +1,16 @@
+// File: insertion_sort_test.go
+// Created Time: 2022-12-12
+// Author: msk397 (machangxinq@gmail.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestInsertionSort(t *testing.T) {
+	nums := []int{4, 1, 3, 1, 5, 2}
+	insertionSort(nums)
+	fmt.Println("After insertion sort, nums =", nums)
+}

en/codes/go/chapter_sorting/merge_sort.go

@@ -0,0 +1,54 @@
+// File: merge_sort.go
+// Created Time: 2022-12-13
+// Author: msk397 (machangxinq@gmail.com)
+
+package chapter_sorting
+
+/* Merge left subarray and right subarray */
+func merge(nums []int, left, mid, right int) {
+	// Left subarray interval is [left, mid], right subarray interval is [mid+1, right]
+	// Create a temporary array tmp to store the merged results
+	tmp := make([]int, right-left+1)
+	// Initialize the start indices of the left and right subarrays
+	i, j, k := left, mid+1, 0
+	// While both subarrays still have elements, compare and copy the smaller element into the temporary array
+	for i <= mid && j <= right {
+		if nums[i] <= nums[j] {
+			tmp[k] = nums[i]
+			i++
+		} else {
+			tmp[k] = nums[j]
+			j++
+		}
+		k++
+	}
+	// Copy the remaining elements of the left and right subarrays into the temporary array
+	for i <= mid {
+		tmp[k] = nums[i]
+		i++
+		k++
+	}
+	for j <= right {
+		tmp[k] = nums[j]
+		j++
+		k++
+	}
+	// Copy the elements from the temporary array tmp back to the original array nums at the corresponding interval
+	for k := 0; k < len(tmp); k++ {
+		nums[left+k] = tmp[k]
+	}
+}
+
+/* Merge sort */
+func mergeSort(nums []int, left, right int) {
+	// Termination condition
+	if left >= right {
+		return
+	}
+	// Divide and conquer stage
+	mid := left + (right - left) / 2
+	mergeSort(nums, left, mid)
+	mergeSort(nums, mid+1, right)
+	// Merge stage
+	merge(nums, left, mid, right)
+}

en/codes/go/chapter_sorting/merge_sort_test.go

@@ -0,0 +1,16 @@
+// File: merge_sort_test.go
+// Created Time: 2022-12-13
+// Author: msk397 (machangxinq@gmail.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestMergeSort(t *testing.T) {
+	nums := []int{7, 3, 2, 6, 0, 1, 5, 4}
+	mergeSort(nums, 0, len(nums)-1)
+	fmt.Println("After merge sort completes, nums = ", nums)
+}

en/codes/go/chapter_sorting/quick_sort.go

@@ -0,0 +1,130 @@
+// File: quick_sort.go
+// Created Time: 2022-12-12
+// Author: msk397 (machangxinq@gmail.com)
+
+package chapter_sorting
+
+// Quick sort
+type quickSort struct{}
+
+// Quick sort (recursion depth optimization)
+type quickSortMedian struct{}
+
+// Quick sort (recursion depth optimization)
+type quickSortTailCall struct{}
+
+/* Sentinel partition */
+func (q *quickSort) partition(nums []int, left, right int) int {
+	// Use nums[left] as the pivot
+	i, j := left, right
+	for i < j {
+		for i < j && nums[j] >= nums[left] {
+			j-- // Search from right to left for the first element smaller than the pivot
+		}
+		for i < j && nums[i] <= nums[left] {
+			i++ // Search from left to right for the first element greater than the pivot
+		}
+		// Swap elements
+		nums[i], nums[j] = nums[j], nums[i]
+	}
+	// Swap the pivot to the boundary between the two subarrays
+	nums[i], nums[left] = nums[left], nums[i]
+	return i // Return the index of the pivot
+}
+
+/* Quick sort */
+func (q *quickSort) quickSort(nums []int, left, right int) {
+	// Terminate recursion when subarray length is 1
+	if left >= right {
+		return
+	}
+	// Sentinel partition
+	pivot := q.partition(nums, left, right)
+	// Recursively process the left subarray and right subarray
+	q.quickSort(nums, left, pivot-1)
+	q.quickSort(nums, pivot+1, right)
+}
+
+/* Select the median of three candidate elements */
+func (q *quickSortMedian) medianThree(nums []int, left, mid, right int) int {
+	l, m, r := nums[left], nums[mid], nums[right]
+	if (l <= m && m <= r) || (r <= m && m <= l) {
+		return mid // m is between l and r
+	}
+	if (m <= l && l <= r) || (r <= l && l <= m) {
+		return left // l is between m and r
+	}
+	return right
+}
+
+/* Sentinel partition (median of three) */
+func (q *quickSortMedian) partition(nums []int, left, right int) int {
+	// Use nums[left] as the pivot
+	med := q.medianThree(nums, left, (left+right)/2, right)
+	// Swap the median to the array's leftmost position
+	nums[left], nums[med] = nums[med], nums[left]
+	// Use nums[left] as the pivot
+	i, j := left, right
+	for i < j {
+		for i < j && nums[j] >= nums[left] {
+			j-- // Search from right to left for the first element smaller than the pivot
+		}
+		for i < j && nums[i] <= nums[left] {
+			i++ // Search from left to right for the first element greater than the pivot
+		}
+		// Swap elements
+		nums[i], nums[j] = nums[j], nums[i]
+	}
+	// Swap the pivot to the boundary between the two subarrays
+	nums[i], nums[left] = nums[left], nums[i]
+	return i // Return the index of the pivot
+}
+
+/* Quick sort */
+func (q *quickSortMedian) quickSort(nums []int, left, right int) {
+	// Terminate recursion when subarray length is 1
+	if left >= right {
+		return
+	}
+	// Sentinel partition
+	pivot := q.partition(nums, left, right)
+	// Recursively process the left subarray and right subarray
+	q.quickSort(nums, left, pivot-1)
+	q.quickSort(nums, pivot+1, right)
+}
+
+/* Sentinel partition */
+func (q *quickSortTailCall) partition(nums []int, left, right int) int {
+	// Use nums[left] as the pivot
+	i, j := left, right
+	for i < j {
+		for i < j && nums[j] >= nums[left] {
+			j-- // Search from right to left for the first element smaller than the pivot
+		}
+		for i < j && nums[i] <= nums[left] {
+			i++ // Search from left to right for the first element greater than the pivot
+		}
+		// Swap elements
+		nums[i], nums[j] = nums[j], nums[i]
+	}
+	// Swap the pivot to the boundary between the two subarrays
+	nums[i], nums[left] = nums[left], nums[i]
+	return i // Return the index of the pivot
+}
+
+/* Quick sort (recursion depth optimization) */
+func (q *quickSortTailCall) quickSort(nums []int, left, right int) {
+	// Terminate when subarray length is 1
+	for left < right {
+		// Sentinel partition operation
+		pivot := q.partition(nums, left, right)
+		// Perform quick sort on the shorter of the two subarrays
+		if pivot-left < right-pivot {
+			q.quickSort(nums, left, pivot-1) // Recursively sort the left subarray
+			left = pivot + 1                 // Remaining unsorted interval is [pivot + 1, right]
+		} else {
+			q.quickSort(nums, pivot+1, right) // Recursively sort the right subarray
+			right = pivot - 1                 // Remaining unsorted interval is [left, pivot - 1]
+		}
+	}
+}

en/codes/go/chapter_sorting/quick_sort_test.go

@@ -0,0 +1,34 @@
+// File: quick_sort_test.go
+// Created Time: 2022-12-12
+// Author: msk397 (machangxinq@gmail.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+// Quick sort
+func TestQuickSort(t *testing.T) {
+	q := quickSort{}
+	nums := []int{4, 1, 3, 1, 5, 2}
+	q.quickSort(nums, 0, len(nums)-1)
+	fmt.Println("After quick sort completes, nums = ", nums)
+}
+
+// Quick sort (recursion depth optimization)
+func TestQuickSortMedian(t *testing.T) {
+	q := quickSortMedian{}
+	nums := []int{4, 1, 3, 1, 5, 2}
+	q.quickSort(nums, 0, len(nums)-1)
+	fmt.Println("After quick sort (median pivot optimization), nums = ", nums)
+}
+
+// Quick sort (recursion depth optimization)
+func TestQuickSortTailCall(t *testing.T) {
+	q := quickSortTailCall{}
+	nums := []int{4, 1, 3, 1, 5, 2}
+	q.quickSort(nums, 0, len(nums)-1)
+	fmt.Println("After quick sort (recursion depth optimization), nums = ", nums)
+}

en/codes/go/chapter_sorting/radix_sort.go

@@ -0,0 +1,60 @@
+// File: radix_sort.go
+// Created Time: 2023-01-18
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+import "math"
+
+/* Get the k-th digit of element num, where exp = 10^(k-1) */
+func digit(num, exp int) int {
+	// Passing exp instead of k can avoid repeated expensive exponentiation here
+	return (num / exp) % 10
+}
+
+/* Counting sort (based on nums k-th digit) */
+func countingSortDigit(nums []int, exp int) {
+	// Decimal digit range is 0~9, therefore need a bucket array of length 10
+	counter := make([]int, 10)
+	n := len(nums)
+	// Count the occurrence of digits 0~9
+	for i := 0; i < n; i++ {
+		d := digit(nums[i], exp) // Get the k-th digit of nums[i], noted as d
+		counter[d]++             // Count the occurrence of digit d
+	}
+	// Calculate prefix sum, converting "occurrence count" into "array index"
+	for i := 1; i < 10; i++ {
+		counter[i] += counter[i-1]
+	}
+	// Traverse in reverse, based on bucket statistics, place each element into res
+	res := make([]int, n)
+	for i := n - 1; i >= 0; i-- {
+		d := digit(nums[i], exp)
+		j := counter[d] - 1 // Get the index j for d in the array
+		res[j] = nums[i]    // Place the current element at index j
+		counter[d]--        // Decrease the count of d by 1
+	}
+	// Use result to overwrite the original array nums
+	for i := 0; i < n; i++ {
+		nums[i] = res[i]
+	}
+}
+
+/* Radix sort */
+func radixSort(nums []int) {
+	// Get the maximum element of the array, used to determine the maximum number of digits
+	max := math.MinInt
+	for _, num := range nums {
+		if num > max {
+			max = num
+		}
+	}
+	// Traverse from the lowest to the highest digit
+	for exp := 1; max >= exp; exp *= 10 {
+		// Perform counting sort on the k-th digit of array elements
+		// k = 1 -> exp = 1
+		// k = 2 -> exp = 10
+		// i.e., exp = 10^(k-1)
+		countingSortDigit(nums, exp)
+	}
+}

en/codes/go/chapter_sorting/radix_sort_test.go

@@ -0,0 +1,18 @@
+// File: radix_sort_test.go
+// Created Time: 2023-01-18
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestRadixSort(t *testing.T) {
+	/* Radix sort */
+	nums := []int{10546151, 35663510, 42865989, 34862445, 81883077,
+		88906420, 72429244, 30524779, 82060337, 63832996}
+	radixSort(nums)
+	fmt.Println("After radix sort completes, nums = ", nums)
+}

en/codes/go/chapter_sorting/selection_sort.go

@@ -0,0 +1,24 @@
+// File: selection_sort.go
+// Created Time: 2023-05-29
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+/* Selection sort */
+func selectionSort(nums []int) {
+	n := len(nums)
+	// Outer loop: unsorted interval is [i, n-1]
+	for i := 0; i < n-1; i++ {
+		// Inner loop: find the smallest element within the unsorted interval
+		k := i
+		for j := i + 1; j < n; j++ {
+			if nums[j] < nums[k] {
+				// Record the index of the smallest element
+				k = j
+			}
+		}
+		// Swap the smallest element with the first element of the unsorted interval
+		nums[i], nums[k] = nums[k], nums[i]
+
+	}
+}

en/codes/go/chapter_sorting/selection_sort_test.go

@@ -0,0 +1,16 @@
+// File: selection_sort_test.go
+// Created Time: 2023-05-29
+// Author: Reanon (793584285@qq.com)
+
+package chapter_sorting
+
+import (
+	"fmt"
+	"testing"
+)
+
+func TestSelectionSort(t *testing.T) {
+	nums := []int{4, 1, 3, 1, 5, 2}
+	selectionSort(nums)
+	fmt.Println("After selection sort completes, nums = ", nums)
+}