int binary_search(int arr[], int k, int left, int right){ //int right = sizeof(arr) / sizeof(arr[0]) - 1;放在这里错误，arr是指针，长度为4个字节，right=0 while (left <= right) { int mid = left + (right - left) / 2;//每次都要改变，所以要循环 if (arr[mid] > k) { right = mid - 1; } else if (arr[mid] < k) { left = mid + 1; } else { return mid; } } return -1;}int main(){ int arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };//初始化数组可以替换 int k = 0; int left = 0; int right = sizeof(arr) / sizeof(arr[0]) - 1;//在哪定义在哪使用 printf("输入需要找到数字\n"); scanf("%d",&k); int ret = binary_search(arr, k, left, right); if (ret == -1) { printf("找不到\n"); } else { printf("找到了,下标是:%d\n", ret); } //int mid = (left+right)/2; return 0;}