text: #include <stdio.h>
  #include <stdlib.h>
  
  #include "stat.h"
  
  int main(int argc, char *argv[])
  {
      double *inputs, result;
  
      if (argc < 2) {
          fprintf(stderr, "usage: %s [numbers]\n", argv[0]);
          return EXIT_FAILURE;
      }
  
      inputs = get_values(argc, argv);
      if (inputs == NULL) {
          fprintf(stderr, "invalid inputs\n");
          return EXIT_FAILURE;
      }
  
      result = mean(inputs, argc - 1);
      printf("%.3g\n", result);
  
      return EXIT_SUCCESS;
  }
  