Solution to the Dwarves and Coins problem

dwarves_and_coins.cpp

/* Dwarves and Coins Solution by Dillon Morse
 * ------------------------------------------
 * Several (M) dwarves have found a goblin's chest with N gold coins and have
 * to divide them. Due to ancient rules governing the allocation of loot to
 * pirates in order of seniority, the oldest dwarf should get one coin more
 * than the next oldest dwarf, and so on, so that the youngest dwarf gets M-1
 * fewer coins than the oldest dwarf. Additionally, no dwarf has to pitch in
 * any coins (ie no negative coins to any dwarfs)
 *
 * Help the dwarves to divide the coins in this way, or tell them that this is
 * impossible.
 *
 * Input
 * -----
 * You are given an integer N (3 <= N <= 1000) for number of coins and an integer
 * M (3 <= M <= N) for number of dwarves, space-separated.
 *
 * Output
 * ------
 * If it is impossible to divide the coins in the way that dwarves want, print
 * -1 (minus one). Otherwise, print the numbers of coins that each dwarf will
 * receive, from oldest to youngest. Separate the numbers with spaces.
 */

#include <iostream>
#include <vector>

using namespace std;

int main() {
  int dwarves, coins, i, total, run;
  vector<int> result;
  cout << "Input:\n";
  cin >> coins >> dwarves;

  run = 0;
  do {
    run += 1;
    total = 0;
    for( i = dwarves + run - 2; i >= run - 1; i-- ) {
      total += i;
    }
  } while( total < coins ); 

  if( total == coins ) {
    for( i = dwarves + run - 2; i >= run - 1; i-- ) {
      result.push_back( i );
    }
  }
  else result.push_back( -1 );

  cout << "\nOutput:\n";
  
  for( i = 0; i < result.size(); i++ ) {
    cout << result[i] << " ";
  }
  cout << '\n';

  return 0;
}