PTA 7-40 文件存储水仙花数

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

// 判断一个数是否为水仙花数
int isNarcissistic(int num) {
    int originalNum = num;
    int digit, sum = 0;
    while (num > 0) {
        digit = num % 10;
        sum += (int)pow(digit, 3);
        num = num / 10;
    }
    return sum == originalNum;
}

int main() {
    int m, n;
    scanf("%d %d", &m, &n);
    FILE *fp = fopen("out.txt", "w");
    if (fp == NULL) {
        perror("Error opening file");
        return 1;
    }
    for (int i = m; i <= n; i++) {
        if (isNarcissistic(i)) {
            fprintf(fp, "%d ", i);
        }
    }
    fclose(fp);
    return 0;
}