enzo.c

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

typedef unsigned long long int numerito;

numerito string_to_uint(char *string) {
  size_t length = strlen(string);
  numerito res = 0;
  for (size_t i = 0; i < length; i++)
    res += string[i] << 8 * i;
  return res;
}

void uint_to_string(char *res, size_t size, numerito num) {
  for (size_t i = 0; i < size; i++)
    res[i] = (num & (0XFF << 8 * i)) >> 8 * i;
}

void print_usage() {
  printf("Usage: enzo [type] [value]\n\n[type] is the type that will be "
         "transformed, can be \"number\" or "
         "\"string\"\n[value] value of the arg\n");
}

int main(int argc, char *argv[]) {
  if (argc < 3) {
    print_usage();
    return 1;
  }
  char *type = argv[1];
  char *value = argv[2];
  if (!strcmp(type, "string")) {
    numerito num = string_to_uint(value);
    printf("%d\n", num);
  } else if (!strcmp(type, "number")) {
    numerito num = atoi(value);
    size_t size = sizeof(num);
    char string_transformed[size];
    uint_to_string(string_transformed, size, num);
    printf("%s\n", string_transformed);
  } else {
    print_usage();
    return 1;
  }
  return 0;
}