Java排序算法速度比较（转载）
public class Sort {
public void swap(int a[], int i, int j) {
int tmp = a[i];
a[i] = a[j];
a[j] = tmp;
}
public int partition(int a[], int low, int high) {
int pivot, p_pos, i;
p_pos = low;
pivot = a[p_pos];
for (i = low + 1; i if (a[i] > pivot) {
p_pos++;
swap(a, p_pos, i);
}
}
swap(a, low, p_pos);
return p_pos;
}
public void quicksort(int a[], int low, int high) {
int pivot;
if (low pivot = partition(a, low, high);
quicksort(a, low, pivot - 1);
quicksort(a, pivot + 1, high);
}
}
public static void main(String args[]) {
int vec[] = new int[] { 37, 47, 23, -5, 19, 56 };
int temp;
//选择排序法(Selection Sort)
long begin = System.currentTimeMillis();
for (int k = 0; k for (int i = 0; i for (int j = i; j if (vec[j] > vec[i]) {
temp = vec[i];
vec[i] = vec[j];
vec[j] = temp;
}
}
}
}
long end = System.currentTimeMillis();
System.out.println("选择法用时为：" + (end - begin));
//打印排序好的结果
for (int i = 0; i System.out.println(vec[i]);
}
// 冒泡排序法(Bubble Sort)
begin = System.currentTimeMillis();
for (int k = 0; k for (int i = 0; i for (int j = i; j if (vec[j + 1] > vec[j]) {
temp = vec[j + 1];
vec[j + 1] = vec[j];
vec[j] = temp;
}
}
}
}
end = System.currentTimeMillis();
System.out.println("冒泡法用时为：" + (end - begin));
//打印排序好的结果
for (int i = 0; i System.out.println(vec[i]);
}
//插入排序法(Insertion Sort)
begin = System.currentTimeMillis();
for (int k = 0; k for (int i = 1; i int j = i;
while (vec[j - 1] vec[j] = vec[j - 1];
j--;
if (j break;
}
}
vec[j] = vec[i];
}
}
end = System.currentTimeMillis();
System.out.println("插入法用时为：" + (end - begin));
//打印排序好的结果
for (int i = 0; i System.out.println(vec[i]);
}
//快速排序法(Quick Sort)
Sort s = new Sort();
begin = System.currentTimeMillis();
for (int k = 0; k s.quicksort(vec, 0, 5);
}
end = System.currentTimeMillis();
System.out.println("快速法用时为：" + (end - begin));
//打印排序好的结果
for (int i = 0; i System.out.println(vec[i]);
}
}
}以下是运行结果：选择法用时为：23456
47
37
23
19
-5冒泡法用时为：17256
47
37
23
19
-5插入法用时为：7856
47
37
23
19
-5快速法用时为：29756
47
37
23
19
-5