二分搜索

二分搜索算法的实现

int BinarySearch(int a[], int n,int x) {    int left = 0, right = n - 1;    int middle = 0;    while (left <= right) {        middle = (left + right) / 2;        if (x == a[middle]) return middle;        else if (x > a[middle]) left = middle + 1;        else right = middle - 1;    }    return -1;}