#include <iostream>
using namespace std;
bool isPerfectSquare(int num) {
    if (num < 2) return true;
 
    long left = 1, right = num;
 
    while (left <= right) {
        long mid = left + (right - left) / 2;
        long square = mid * mid;
 
        if (square == num)
            return true;
        else if (square > num)
            right = mid - 1;
        else
            left = mid + 1;
    }
 
    return false;
}
 
int main() {
    int num = 16;
    if (isPerfectSquare(num))
        cout << "true\n";
    else
        cout << "false\n";
 
    return 0;
}
 

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