Program to obtain month name from the corresponding index.

getmonth.c

/*
 ============================================================================
 Name        : getmonth.c
 Author      : Gonzalo G. Fernandez
 Email		 : ggfernandez@unbosque.edu.co
 Institution : Universidad El Bosque
 Year		 : 2022
 Version     : 1.0
 Copyright   : License MIT
 Description : Program to obtain month name from the corresponding index.
 ============================================================================
 */

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

//! Month list
const char *month_list[12] = {
  "January", "February", "March", "April", "May", "June", "July",
  "August", "September", "October", "November", "December"};

int main(int argc, char *argv[]){
  printf("Convert from month index to month name:\n");

  // Check for arguments
  if (argc < 2){
    printf("ERROR: One argument exected (month number).\n");
    return 1;
  }

  int month_index; // Store input month index

  for (int i=1; i<argc; i++){
    // Convert argument string to integer
    month_index = atoi(argv[i]);
    // Check for valid integer (between 1 and 12)
    if (month_index <= 0 || month_index > 12){
      printf("ERROR: Argument number %d (%d) is not a valid month.\n", i, month_index);
      return 1;
    } else {
      // Output the corresponding month name
      printf("%d: %s\n", month_index, *(month_list + month_index-1));
    }
  }

  return 0;
}