#include <stdio.h>
#include <math.h>

int isPerfectSquare(int num) {
    if (num < 0) {
        return 0; // 负数不是完全平方数
    }
    int sqrtNum = (int)sqrt(num); // 计算平方根并取整
    return (sqrtNum * sqrtNum == num); // 判断平方根的平方是否等于原数
}

int main() {
    int num;
    printf("Enter a number: ");
    scanf("%d", &num);

    if (isPerfectSquare(num)) {
        printf("%d is a perfect square.\n", num);
    } else {
        printf("%d is not a perfect square.\n", num);
    }

    return 0;
}