How to simplify a problem to get the names of the months of the year?

Question

I am beginning to program in C and I realized this problem whose statement is the following:

Write an exercise that asks the user for a one-month number and prints the name of the month on the screen. For example, the user enters 1 and the program writes "January". If you enter a number that does not match any month, you should write an appropriate error message on the screen.

For now, I only know the basics (if, else...), so I did so:

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

int main()
{
    int mes;
    printf("Numero do mes: \n");
    scanf("%d",&mes);
    if (mes == 1)
        printf("Janeiro\n");
    else if (mes == 2)
        printf("Fevereiro\n");
    else if (mes == 3)
        printf("Marco\n");
    else if (mes == 4)
        printf("Abril\n");
    else if (mes == 5)
        printf("Maio\n");
    else if (mes == 6)
        printf("Junho\n");
    else if (mes == 7)
        printf("Julho\n");
    else if (mes == 8)
        printf("Agosto\n");
    else if (mes == 9)
        printf("Setembro\n");
    else if (mes == 10)
        printf("Outubro\n");
    else if (mes == 11)
        printf("Novembro\n");
    else if (mes == 12)
        printf("Dezembro\n");
    else if ((mes<1) || (mes>12))
        printf("Erro\n");

    return 0;

}

How can I solve this same problem with a more simplified code?

Answer 1

Some things are left over, but the biggest simplification is to use a array in place of a if. You can put all the names on this array and access through its index according to typing. Validation needs to be done first. Note that I removed some redundancy, after all simplification entail this.

#include <stdio.h>

int main() {
    int mes;
    printf("Numero do mes: ");
    scanf("%d", &mes);
    if (mes < 1 || mes > 12) {
        printf("\nErro");
        return 0;
    }
    printf("\n%s", (char *[12]){ "Janeiro", "Fevereiro", "Marco", "Abril", "Maio", "Junho", "Julho", "Agosto", "Setembro", "Outubro", "Novembro", "Dezembro" }[mes - 1]);
}

Behold working in the ideone. And in the repl it.. Also put on the Github for future reference.

Answer 2

Store months in an array: const char *strings[] = {"Janeiro","Fevereiro"...};, and access the respective month with user input:

printf("Numero do mes: \n");
scanf("%d",&mes);

printf("%s", meses[mes-1]);

Answer 3

 #include <stdio.h>

 int main() {
    int mes;
    printf("Numero do mes: ");
    scanf("%d", &mes);
    const char *meses[] = {"Janeiro", ...};

    for(int i = 0; i < 12; i++) {
        if(mes == i) {
            printf(meses[i]);
        }
    }
 }