Java中实现二分查找和快速排序
时间: 2023-04-06 12:03:18 浏览: 79
Java实现二分查找的代码如下:
```
public static int binarySearch(int[] arr, int target) {
int left = 0, right = arr.length - 1;
while (left <= right) {
int mid = (left + right) / 2;
if (arr[mid] == target) {
return mid;
} else if (arr[mid] < target) {
left = mid + 1;
} else {
right = mid - 1;
}
}
return -1;
}
```
Java实现快速排序的代码如下:
```
public static void quickSort(int[] arr, int left, int right) {
if (left >= right) {
return;
}
int pivot = arr[(left + right) / 2];
int index = partition(arr, left, right, pivot);
quickSort(arr, left, index - 1);
quickSort(arr, index, right);
}
private static int partition(int[] arr, int left, int right, int pivot) {
while (left <= right) {
while (arr[left] < pivot) {
left++;
}
while (arr[right] > pivot) {
right--;
}
if (left <= right) {
swap(arr, left, right);
left++;
right--;
}
}
return left;
}
private static void swap(int[] arr, int left, int right) {
int temp = arr[left];
arr[left] = arr[right];
arr[right] = temp;
}
```