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

#define FALSE 0
#define TRUE !FALSE

void main (void)
{
   int numbers[20] = {0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0};
   int i,j;
   int temp;
   int match;

   for (i = 0;i < 20;i++)
   {
      temp = 0;

      while ((temp < 10) || (temp > 100))
      {
         printf("Enter a number (%i to go, 999 to quit: ",20-i);
         scanf("%i", &temp);
         if (temp > 998)
            exit(0);
      }

      match = FALSE;

      for (j=0;j < 20;j++)
      {
         if ((temp == numbers[j]) && (numbers[j] != 0))
         {
            match = TRUE;
            break;
         }

      }


      if (!match)
      {
         printf("A new number! : %i\n", temp);
         numbers[i] = temp;
      }

   }

}