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

#define MAX_GROUPS      22

#ifdef DEBUG
#define PRINT(x) printf x
#else
#define PRINT(x)
#endif

typedef struct BIGNUM
{
  int sign;
  int num[MAX_GROUPS];
} BIGNUM;

char *revstr(char *s)
{
  size_t len = strlen(s);
  char *p, *q, *t = s;
  char ch;
  p = s;
  q = p + len - 1;
  while(p < q)
  {
    ch   = *p;
    *p++ = *q;
    *q-- = ch;
  }
  return t;
}

void MakeBigNum(BIGNUM *b, char *s)
{
  int idx = 0;
  int count = 0;
  int mult;
  BIGNUM t = {0};

  memcpy(b, &t, sizeof t);

  revstr(s);
  mult = 1;

  while(*s && *s != '-')
  {
    b->num[idx] += mult * (*s - '0');
    mult *= 10;
    ++count;
    if(count % 3 == 0)
    {
      mult = 1;
      ++idx;
    }
    ++s;
  }

  b->sign = (*s == '-') ? -1 : 1;
}

void Expand(int i)
{
  char *digit[] =
  {
    "one",      "two",  "three",        "four",
    "five",     "six",  "seven",        "eight",        "nine"
  };
  char *teen[] =
  {
    "ten",      "eleven",       "twelve",       "thirteen",     "fourteen",
    "fifteen",  "sixteen",      "seventeen",    "eighteen",     "nineteen"
  };
  char *ty[] =
  {
    "twenty",   "thirty",       "forty",        "fifty",        "sixty",
    "seventy",  "eighty",       "ninety"
  };

  if(i >= 100)
  {
    printf("%s hundred %s ", digit[i / 100 - 1], i % 100 ? "and" : "");
    i %= 100;
  }
  if(i < 20 && i >= 10)
  {
    printf("%s", teen[i - 10]);
  }
  else
  {
    if(i >= 20)
    {
      printf("%s ", ty[i / 10 - 2]);
      i %= 10;
    }
    if(i > 0)
    {
      printf("%s", digit[i - 1]);
    }
  }
}

void PrintBigNum(BIGNUM *b)
{
  char *Words[MAX_GROUPS] =
  {
    "",
    "thousand",
    "million",
    "billion",
    "trillion",
    "quadrillion",
    "pentillion",
    "hexillion",
    "heptillion",
    "octillion",
    "nonillion",
    "decillion",
    "monodecillion",
    "duodecillion",
    "tertiadecillion",
    "tetradecillion",
    "quindecillion",
    "sexadecillion",
    "septadecillion",
    "octadecillion",
    "nonadecillion",
    "icosillion"
  };
  int dirty = 0;
  int count = MAX_GROUPS - 1;
  if(b->sign == -1)
  {
    printf("minus ");
  }

  while(count >= 0)
  {
    if(b->num[count] > 0)
    {
      dirty = 1;
      Expand(b->num[count]);
      printf(" %s ", Words[count]);
    }
    --count;
  }
  if(!dirty)
    printf("zero");
  printf(".\n");
}

int main(int argc, char **argv)
{
  BIGNUM b;
  if(argc > 1)
  {
    MakeBigNum(&b, argv[1]);
    PrintBigNum(&b);
  }
  return 0;
}