写一个程序统计从1到N这N个数中，以下三个条件至少满足之一的数字x个数。

#include <stdio.h>

int isprime(int m) {
    int f = 1;
    for (int i = 2; i < m / 2; i++) {
        if (m % i == 0) {
            f = 0;
            break;
        }
    }
    return f;
}

int isse(int m) {
    int f = 1;
    if (m % 7 != 0)
        f = 0;

    return f;
}
int ishuiwen(int num) {
    int s = num;
    int y = 0;
    while (s > 0) {
        y = y * 10 + s % 10;
        s = s / 10;
    }
    if (y == num)
        return 1;
    else
        return 0;
}

int main()
{
    int n;
    int count = 0;
    scanf("%d", &n);
    //int k = isprime(n);
    for (int i = 1; i <= n; i++) {

        if (ishuiwen(i) || isse(i) || isprime(i)) {
            count++;

        }

    }
    printf("%d\n", count);
    return 0;
}