冒泡排序
一语中的：丢一把沙子，轻的物体往上浮。
基本思想：通过无序区中相邻记录关键字间的比较和位置的交换,使关键字最小的记录如气泡一般逐渐往上“漂浮”直至“水面”。
代码示例：
import java.util.Arrays;
public class BubbleSort {
public int[] bubbleSort(int[] array) {
int length = array.length;
boolean swapped = true;
int compareCount = 0;
do {
swapped = false;
for (int i = 0; i < length - 1; i++) {
System.out.println("compare(" + array[i] + "," + array[i + 1] + ")");
if (array[i] > array[i + 1]) {
int temp = array[i];
array[i] = array[i + 1];
array[i + 1] = temp;
swapped = true;
}
compareCount++;
System.out.println("第" + i + "趟 array=" + Arrays.toString(array));
}
} while (swapped);
System.out.println("冒泡排序比较次数=" + compareCount);
return array;
}
public int[] bubbleSort2(int[] array) {
int length = array.length;
int compareCount = 0;
for(int j = 0; j < length - 1; j++){
for(int i = 0; i < length - j - 1; i++){
System.out.println("compare(" + array[i] + "," + array[i + 1] + ")");
if(array[i] > array[i + 1]){
int temp = array[i];
array[i] = array[i + 1];
array[i + 1] = temp;
}
compareCount++;
}
System.out.println("第" + j + "趟 array=" + Arrays.toString(array));
}
System.out.println("冒泡排序比较次数=" + compareCount);
return array;
}
}