常见的排序算法

package com.h.sort;

public class Sort {
public static void main(String[] args) {
int[] nums = { 3, 1, 4, 2, 6, 5 };
int[] bubbleSortNums = bubbleSort(nums);
for (int i = 0; i < bubbleSortNums.length; i++) {
System.out.println(bubbleSortNums[i]);
}

}

// 冒泡排序(降序排列)
public static int[] bubbleSort(int[] nums) {
int temp;// 记录临时中间值
int size = nums.length;// 数组大小
for (int i = 0; i < size - 1; i++) {
for (int j = i + 1; j < size; j++) {
if (nums[i] < nums[j]) {
temp = nums[i];
nums[i] = nums[j];
nums[j] = temp;
}
}
}
return nums;
}

// 快速排序
public static void quickSort(int[] numbers, int start, int end) {
if (start < end) {
int base = numbers[start]; // 选定的基准值（第一个数值作为基准值）
int temp; // 记录临时中间值
int i = start, j = end;
do {
while ((numbers[i] < base) && (i < end))
i++;
while ((numbers[j] > base) && (j > start))
j--;
if (i <= j) {
temp = numbers[i];
numbers[i] = numbers[j];
numbers[j] = temp;
i++;
j--;
}
} while (i <= j);
if (start < j)
quickSort(numbers, start, j);
if (end > i)
quickSort(numbers, i, end);
}
}

// 选择排序
public static void selectSort(int[] numbers) {
int size = numbers.length, temp;
for (int i = 0; i < size; i++) {
int k = i;
for (int j = size - 1; j > i; j--) {
if (numbers[j] < numbers[k])
k = j;
}
temp = numbers[i];
numbers[i] = numbers[k];
numbers[k] = temp;
}
}

// 插入排序
// @param numbers
public static void insertSort(int[] numbers) {
int size = numbers.length, temp, j;
for (int i = 1; i < size; i++) {
temp = numbers[i];
for (j = i; j > 0 && temp < numbers[j - 1]; j--)
numbers[j] = numbers[j - 1];
numbers[j] = temp;
}
}

// 归并排序
public static void mergeSort(int[] numbers, int left, int right) {
int t = 1;// 每组元素个数
int size = right - left + 1;
while (t < size) {
int s = t;// 本次循环每组元素个数
t = 2 * s;
int i = left;
while (i + (t - 1) < size) {
merge(numbers, i, i + (s - 1), i + (t - 1));
i += t;
}
if (i + (s - 1) < right)
merge(numbers, i, i + (s - 1), right);
}
}

// 归并算法实现
private static void merge(int[] data, int p, int q, int r) {
int[] B = new int[data.length];
int s = p;
int t = q + 1;
int k = p;
while (s <= q && t <= r) {
if (data[s] <= data[t]) {
B[k] = data[s];
s++;
} else {
B[k] = data[t];
t++;
}
k++;
}
if (s == q + 1)
B[k++] = data[t++];
else
B[k++] = data[s++];
for (int i = p; i <= r; i++)
data[i] = B[i];
}

}