Vowels Sample answer

vowels.c

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

#define TRUE 1
#define FALSE 0

#define LENGTH_LIMIT 1000

int is_char_vowel(char c) {
  switch (c) {
    case 'a':
    case 'e':
    case 'i':
    case 'o':
    case 'u':
      return TRUE;
    default:
      return FALSE;
  }
}

int main(int argc, char **argv) {
  int i;
  char current_char;
  char *vowel_order = "aeiou";
  char last_vowel;
  int last_vowel_idx = -1;

  int is_correct;

  for (i = 0, is_correct = TRUE; i < LENGTH_LIMIT; i++) {
    current_char = argv[1][i];
    if (current_char == '\0') {
      break;
    }

    if (current_char == last_vowel) {
      continue;
    }

    if (is_char_vowel(current_char)) {
      if (
        last_vowel_idx != -1 &&
        current_char != vowel_order[last_vowel_idx + 1]
      ) {
        is_correct = FALSE;
        break;
      }

      last_vowel = current_char;
      last_vowel_idx = last_vowel_idx == -1 ? 0 : last_vowel_idx + 1;
    }
  }

  if (!is_correct || last_vowel_idx != 4) {
    printf("False\n");

    return 0;
  }

  printf("True\n");

  return 0;
}

Given a word, check if it has all vowels in order (a, e, i, o, u). The words are only provided in lower case.
Example:
facetious => true
precarious => false
apple => false