#include <arpa/inet.h>
#include <stdio.h>

static int ip_version(const char *src) {
    char buf[INET6_ADDRSTRLEN];
    if (inet_pton(AF_INET, src, buf)) {
        return 4;
    } else if (inet_pton(AF_INET6, src, buf)) {
        return 6;
    }
    return -1;
}

int main(int argc, char *argv[]) {
    for (int i = 1; i < argc; ++i) {
        printf("%s\t%d\n", argv[i], ip_version(argv[i]));
    }

    return 0;
}