Calculate Square Root

SquareRoot.java

public class Solution {
    public int sqrt(int x) {
        long low = 1;
        long high = x/2;
        if (x == 0){
            return 0;
        } 
        if (x < 4){
            return 1;
        } 
        
        while (low <= high){
            long mid = (low + high) /2;
            if (mid == x/mid){
                return (new Long(mid).intValue());
            }
            
            if (mid < x/mid){
                low = mid+1;
            }
            else{
                high = mid-1;
            }
        }
        
        return (new Long(low-1).intValue());
    }
}