[leetcode] Sqrt(x)

Implement int sqrt(int x).

Compute and return the square root of x.

class Solution {public:    int sqrt(int x) {// Start typing your C/C++ solution below// DO NOT write int main() functionif(x<=0)return 0;if(x==1)return 1;int left=1,right=x/2;int middle=0;while(left<=right){middle=((right-left)>>1)+left;int temp=middle*middle;if(temp>x || temp/middle!=middle)right=middle-1;else if(middle*middle<x && temp/middle==middle)left=middle+1;elsereturn middle;}return right;}};