Sqrt(x)

Link

Just the used the binary search algorithm to find the sqrt. Had to account for large numbers, so I used long instead of int.

Full Solution in Java:

 public class Solution {
    public int mySqrt(int x) {
        
        
        int low = 0;
        int high = x/2+1;
        long mid = (low+high)/2;
        
        while(low<=high){
            long test = mid*mid;
            
            if(test==(long)x){
                return (int)mid;
            }
            
            if(test<(long)x){
                low = (int)mid+1;
                mid = (low+high)/2;
            }
            else if(test>(long)x){
                high = (int)mid-1;
                mid = (low+high)/2;
            }
        }
        
        return (int)mid;
    }
}