бинарные 10

#include <stdio.h>

int sol(int n);
int sol(int n)
{
    return !(n & (n - 1)) && (n % 3 == 1);
}

int main(void)
{
    int n;
    if (scanf("%d", &n) != 1)
    {
        printf("cannot read n!\n");
    }

    if (sol(n)) {
        printf("is a power of 4\n", &n);
    }
    else {
        printf("is not a power of 4\n", &n);
    }

    return 0;
}