content: package honey;
  
  import java.io.FileReader;
  import java.io.FileWriter;
  import java.io.IOException;
  import java.util.ArrayList;
  import java.util.Scanner;
  import java.util.StringTokenizer;
  
  public class Honey {
      public static void main(String[] args) throws IOException {
          ArrayList<Long> data = new ArrayList<>();
          FileReader file = new FileReader("input.txt");
          Scanner sc = new Scanner(file);
          StringTokenizer st = new StringTokenizer(sc.nextLine(), " ");
          while (st.hasMoreTokens()){
              data.add(Long.valueOf(st.nextToken()));
          }
          long n = data.get(0);
          long v = data.get(1);
          long k = data.get(2);
  
          boolean empty = false;
          long honey = 0;
          long minus = k;
  
          for(int i = 0; i < n; i++){
              if(i == 0){
                  honey += v;
              }else {
                  if(minus >= v){
                      minus = v;
                      empty = true;
                  }
                  honey += (v - minus);
                  minus += k;
              }
          }
  
          String result = (empty) ? "NO " + honey : "YES " + honey;
  
          FileWriter out = new FileWriter("output.txt");
          out.write(result);
          out.close();
      }
  }
  