Merge remote-tracking branch 'upstream/master'

c-cpp/11_sorts/sorts.c

@@ -0,0 +1,139 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdbool.h>
+
+struct array {
+	int size;
+	int used;
+	int *arr;
+};
+
+void dump(struct array *array)
+{
+	int idx;
+	
+	for (idx = 0; idx < array->used; idx++)
+		printf("[%02d]: %08d\n", idx, array->arr[idx]);
+}
+
+void alloc(struct array *array)
+{
+	array->arr = (int *)malloc(array->size * sizeof(int));
+}
+
+void bubble_sort(struct array *array)
+{
+	int i, j;
+
+	if (array->used <= 1)
+		return;
+
+	for (i = 0; i < array->used; i++) {
+		bool has_swap = false;
+		for (j = 0; j < array->used - i - 1; j++) {
+			if (array->arr[j] > array->arr[j+1]) {
+				int tmp;
+				tmp = array->arr[j];
+				array->arr[j] = array->arr[j+1];
+				array->arr[j+1] = tmp;
+				has_swap = true;
+			}
+
+		}
+		if (!has_swap)
+			break;
+	}
+}
+
+void bubble_sort_test()
+{
+	int idx;
+	struct array ten_int = {10, 0, NULL};
+
+	alloc(&ten_int);
+	for (idx = 0; idx < 10; idx++)
+		ten_int.arr[idx] = 30 - idx;
+	ten_int.used = 10;
+	dump(&ten_int);
+	bubble_sort(&ten_int);
+	dump(&ten_int);
+}
+
+void insertion_sort(struct array *array)
+{
+	int i, j;
+
+	if (array->used <= 1)
+		return;
+
+	for (i = 1; i < array->used; i++) {
+		int val = array->arr[i];
+
+		for (j = i - 1; j >= 0; j--) {
+			if (val < array->arr[j])
+				array->arr[j+1] = array->arr[j]; 
+			else
+				break;
+		}
+		array->arr[j+1] = val;
+	}
+}
+
+void insertion_sort_test()
+{
+	int idx;
+	struct array ten_int = {10, 0, NULL};
+
+	alloc(&ten_int);
+	for (idx = 0; idx < 10; idx++)
+		ten_int.arr[idx] = 30 - idx;
+	ten_int.used = 10;
+	dump(&ten_int);
+	insertion_sort(&ten_int);
+	dump(&ten_int);
+}
+
+void selection_sort(struct array *array)
+{
+	int i, j;
+
+	if (array->used <= 1)
+		return;
+
+	for (i = 0; i < array->used - 1; i++) {
+		int tmp, idx = i;
+
+		for (j = i + 1; j < array->used; j++)
+			if (array->arr[j] < array->arr[idx])
+				idx = j;
+
+		if (idx == i)
+			continue;
+
+		tmp = array->arr[i];
+		array->arr[i] = array->arr[idx];
+		array->arr[idx] = tmp;
+	}
+}
+
+void selection_sort_test()
+{
+	int idx;
+	struct array ten_int = {10, 0, NULL};
+
+	alloc(&ten_int);
+	for (idx = 0; idx < 10; idx++)
+		ten_int.arr[idx] = 30 - idx;
+	ten_int.used = 10;
+	dump(&ten_int);
+	selection_sort(&ten_int);
+	dump(&ten_int);
+}
+
+int main()
+{
+	//bubble_sort_test();
+	//selection_sort_test();
+	insertion_sort_test();
+	return 0;
+}

go/11_sorts/Sort.go

@@ -1,54 +1,66 @@
 package _1_sorts
 
-func BubbleSort(a []int) {
-	arrLen := len(a)
-	if arrLen <= 1 {
+/*
+冒泡排序、插入排序、选择排序
+ */
+
+//冒泡排序，a是数组，n表示数组大小
+func BubbleSort(a []int, n int) {
+	if n <= 1 {
 		return
 	}
-	for i := arrLen - 1; i > 0; i-- {
-		for j := 0; j < i; j++ {
+	for i := 0; i < n; i++ {
+		// 提前退出标志
+		flag := false
+		for j := 0; j < n-i-1; j++ {
 			if a[j] > a[j+1] {
-				tmp := a[j+1]
-				a[j+1] = a[j]
-				a[j] = tmp
+				a[j], a[j+1] = a[j+1], a[j]
+				//此次冒泡有数据交换
+				flag = true
 			}
 		}
+		// 如果没有交换数据，提前退出
+		if !flag {
+			break
+		}
 	}
 }
 
-func InsertSort(a []int) {
-	arrLen := len(a)
-	if arrLen <= 1 {
+// 插入排序，a表示数组，n表示数组大小
+func InsertionSort(a []int, n int) {
+	if n <= 1 {
 		return
 	}
-	for i := 1; i < arrLen; i++ {
-		v := a[i]
+	for i := 1; i < n; i++ {
+		value := a[i]
 		j := i - 1
+		//查找要插入的位置并移动数据
 		for ; j >= 0; j-- {
-			if a[j] > v {
+			if a[j] > value {
 				a[j+1] = a[j]
+			} else {
+				break
 			}
 		}
-		a[j+1] = v
+		a[j+1] = value
 	}
 }
 
-func SelectionSort(a []int) {
-	arrLen := len(a)
-	if arrLen <= 1 {
+// 选择排序，a表示数组，n表示数组大小
+func SelectionSort(a []int, n int) {
+	if n <= 1 {
 		return
 	}
-	for i := 0; i < arrLen; i++ {
+	for i := 0; i < n; i++ {
+		// 查找最小值
 		minIndex := i
-		for j := i + 1; j < arrLen; j++ {
+		for j := i + 1; j < n; j++ {
 			if a[j] < a[minIndex] {
 				minIndex = j
 			}
 		}
-		if minIndex != i {
-			tmp := a[minIndex]
-			a[minIndex] = a[i]
-			a[i] = tmp
-		}
+		// 交换
+		a[i], a[minIndex] = a[minIndex],a[i]
+
 	}
 }

java/11_sorts/Sorts.java

@@ -58,6 +58,9 @@ public class Sorts {
         }
       }
 
+      if (minIndex == i)
+        continue;
+
       // 交换
       int tmp = a[i];
       a[i] = a[minIndex];

java/14_sorts/CountingSort.java

@@ -0,0 +1,53 @@
+package sorts;
+
+/**
+ * 计数排序
+ *
+ * Author: ZHENG
+ */
+public class CountingSort {
+
+  // 计数排序，a是数组，n是数组大小。假设数组中存储的都是非负整数。
+  public static void countingSort(int[] a, int n) {
+    if (n <= 1) return;
+
+    // 查找数组中数据的范围
+    int max = a[0];
+    for (int i = 1; i < n; ++i) {
+      if (max < a[i]) {
+        max = a[i];
+      }
+    }
+
+    // 申请一个计数数组c，下标大小[0,max]
+    int[] c = new int[max + 1];
+    for (int i = 0; i < max + 1; ++i) {
+      c[i] = 0;
+    }
+
+    // 计算每个元素的个数，放入c中
+    for (int i = 0; i < n; ++i) {
+      c[a[i]]++;
+    }
+
+    // 依次累加
+    for (int i = 1; i < max + 1; ++i) {
+      c[i] = c[i-1] + c[i];
+    }
+
+    // 临时数组r，存储排序之后的结果
+    int[] r = new int[n];
+    // 计算排序的关键步骤了，有点难理解
+    for (int i = n - 1; i >= 0; --i) {
+      int index = c[a[i]]-1;
+      r[index] = a[i];
+      c[a[i]]--;
+    }
+
+    // 将结果拷贝会a数组
+    for (int i = 0; i < n; ++i) {
+      a[i] = r[i];
+    }
+  }
+
+}