#include <stdio.h>
#include <stdlib.h>
#define MAX 31

void maiuscula(char *s);

int main() {
    char vet[MAX];
    printf("digite: ");
    gets(vet);
    maiuscula(vet);
    printf("%s", vet);

    printf("\n\n");
    system("pause");
}

void maiuscula(char *s){
     do{
         if(*s >= 'a' && *s <= 'z')
               *s = (*s - 32);// 32 e a diferenca entre as minusculas e as maiusculas
         s++;
     }while(*s);
}