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