Java 普通算法研究一

冒泡排序：

class BubbleSort {


public void sort(int[] array) {


for (int i = 1; i < array.length; i++) {


for (int j = 0; j < array.length - 1; j++) {


if (array[j] > array[j + 1]) {
int temp = array[j];
array[j] = array[j + 1];
array[j + 1] = temp;
}


}


}


}
}

快速排序

class Buicksort {


public int data[];


private int partition(int sortArray[], int low, int hight)


{


int key = sortArray[low];


while (low < hight)


{


while (low < hight && sortArray[hight] >= key)


hight--;


sortArray[low] = sortArray[hight];


while (low < hight && sortArray[low] <= key)


low++;


sortArray[hight] = sortArray[low];


}


sortArray[low] = key;


return low;


}


public void sort(int low, int hight)


{


if (low < hight)


{


int result = partition(data, low, hight);


sort(low, result - 1);


sort(result + 1, hight);


}


}


public void display()


{


for (int i = 0; i < data.length; i++)


{


System.out.print(data[i]);


System.out.print(" ");


}


}


}

测试main函数：

BubbleSort bubbleSort = new BubbleSort();
int[] array = {44,22,2,32,54,22,88,77,99,11};
long t1 = System.currentTimeMillis();
bubbleSort.sort(array);
for (int i = 0; i < array.length; i++) {
System.out.print(array[i]);
System.out.print(" ");
}
long t2 = System.currentTimeMillis();
System.out.println(t2-t1);
System.out.println("\n--------------------------");

Buicksort buicksort = new Buicksort();
int data[] = {44,22,2,32,54,22,88,77,99,11};
buicksort.data = data;
long t3 = System.currentTimeMillis();
buicksort.sort(0, buicksort.data.length-1);
buicksort.display();
long t4 = System.currentTimeMillis();
System.out.println(t4-t3);

System.out.println("\n--------------------------");
int arraydata[] = {44,22,2,32,54,22,88,77,99,11};
long t5 = System.currentTimeMillis();
Arrays.sort(arraydata);
for (int i = 0; i < array.length; i++) {
System.out.print(arraydata[i]);
System.out.print(" ");
}
long t6 = System.currentTimeMillis();
System.out.println(t6-t5);

通过运行结果得出：还是jdk自带的方法运行效果最高！