// Helene Martin, CSE 142
// Helps a user practice their addition of numbers 1 - 50.
// The game ends after 3 wrong answers are given.

// development strategy:
// we started by getting a single game to work
// we put that game in a method
// we called that game in a while loop
// we noticed we needed information from the method so returned points

import java.util.*;
public class AdditionGame {
   public static void main(String[] args) {
      Scanner console = new Scanner(System.in);
      Random rand = new Random();
      
      int misses = 0;
      int points = 0;
      while (misses < 3) {
         int result = playGame(rand, console);
         
         if (result == 1) {
            points++;
         } else {
            misses++;
         }
      }
      System.out.println("You earned " + points + " total points.");
   }
   
   // Prompts the user with an adding problem with 2 - 5 operands
   // and returns the number of points received (0 or 1).
   public static int playGame(Random rand, Scanner console) {
      int operands = rand.nextInt(4) + 2;
      int answer = 0;
      for (int i = 0; i < operands - 1; i++) {
         int operand = rand.nextInt(50) + 1;
         answer += operand;
         System.out.print(operand + " + ");
      }
      
      int operand = rand.nextInt(50) + 1;
      answer += operand;
      System.out.print(operand);
      
      // for debugging: System.out.print(" = " + answer);
      System.out.print(" = ");
      int userAns = console.nextInt();
      
      if (userAns == answer) {
         return 1;
      } else {
         System.out.println("Wrong!  The answer was " + answer);
         return 0;
      }
   }
}