leetcode Sqrt(x)

 代码

利用二分法

class Solution {
public:
    int sqrt(int x) {
        long long i = 0;
        long long j = x/2+1;
        while(i<=j)
        {
            long long mid = (i+j)/2;
            long long temp = mid*mid;
            if(temp==x)
                return mid;
            else if(temp>x)
                j = mid - 1;
            else
                i = mid + 1;
            
        }
        
        return j;
    }
};