C++

1 class Solution { 2 public: 3     /** 4      * @param x: An integer 5      * @return: The sqrt of x 6      */ 7     int sqrt(int x) { 8         // write your code here 9         if (x<=1) {10             return x;11         }12         int left = 1;13         int right = x;14         while (left <= right) {15             int mid = left + ((right - left) >> 1);16             if (mid == x/mid) {17                 return mid;18             }19             else if (mid < x/mid) {20                 left = mid + 1;21             } else {22                 right = mid - 1;23             }24         }25         return right;26     }27 };