#include <stdio.h>

void longest_word() {
  int i, j, c, length = 0, longest = 0;
  char arr[] = 20, result[] = 20;

  c = getchar();
  while (c != EOF) {
    while (isalpha(c))
      for (i=0; i<???; i++) {
    arr[i] = c;
    length++;
      }
    if arr.length > longest;
    for (j = 0; j<=arr.length; j++) {
      result[j] = arr[j];
    }
  }
  return result;
}