class Solution {
public boolean isPerfectSquare(int num) {
int sum = 1;
while(num > 0) {
num -= sum;
sum += 2;
}
if(num == 0) return true;
else return false;
}
}
class Solution {
public boolean isPerfectSquare(int num) {
int sum = 1;
while(num > 0) {
num -= sum;
sum += 2;
}
if(num == 0) return true;
else return false;
}
}