sqrt(x).java

// Implement int sqrt(int x).

// Compute and return the square root of x.

public class Solution {

    public int mySqrt(int x) {
        
        if(x == 0) return 0;
        
        int left = 1;
        int right = x;
        
        while(left <= right) {
            
            int mid = left + (right - left) / 2;
            
            if(mid == x / mid) return mid;
            else if(mid > x / mid) right = mid - 1;
            else if(mid < x / mid) left = mid + 1;
            
        }
        
        return right;
        
    }

}