// distinct1000: print the number of distinct numbers between 0 and 999 appearing
//               in the input
// For instance, "5 8 8 4 8 5" has three distinct input values (4, 5, and 8).
//
// Robert W. Hasker, March 2016
//

#include <iostream>
using namespace std;

constexpr int POSSIBLE_INPUTS = 1000;

// Reads integers between 0 and POSSIBLE_INPUTS - 1 and marks each distinct
//    integer read. numbers_found must be allocated with POSSIBLE_INPUTS items.
void read(bool numbers_found[]) 
{
   for(int i = 0; i < POSSIBLE_INPUTS; ++i)
      numbers_found[i] = false;
   int num;
   cin >> num;
   while ( cin ) {
      numbers_found[num] = true;
      cin >> num;
   }
}

// Returns the number of true's in numbers_found where numbers_found has
//    POSSIBLE_INPUTS items.
int trueCount(bool numbers_found[]) 
{
   int count = 0;
   for(int i = 0; i < POSSIBLE_INPUTS; ++i) {
      if ( numbers_found[i] )
         ++count;
   }
   return count;
}

// main program: reads numbers and prints the count
int main() 
{
   bool numbers_found[POSSIBLE_INPUTS];
   read(numbers_found);
   int distinct_integers = trueCount(numbers_found);
   cout << "Number of distinct integers: " << distinct_integers << endl;
   return 0;
}