#include <stdio.h>
#include <stdlib.h>
#include <string.h>

void nullkey(void)
{
    printf("%sType: ./CrackMe <password>%s\n");
    exit(1);
}

void youwin(void)
{
    printf("%sYou win!%s\n");
    exit(1);
}

int main(int argc, char *argv[])
{
    if (argv[1] == NULL) nullkey();

    char keytrue[] = "tfoib";
    char *key = argv[1];
    char *keystorage;

    int i;
    for (i=0; i<strlen(keytrue); i++) keytrue[i]--;
    keystorage = keytrue;

    if (strcmp(keystorage,key) == 0 ) { youwin(); } else { printf("%sChave invalida!\n%s"); }

    return 0;
}