// Asks the user to do adding problems and scores them.
import java.util.*;

public class AddingGame {
   public static void main(String[] args) {
      Scanner console = new Scanner(System.in);
      Random rand = new Random();

      // play until user gets 3 wrong
      int points = 0;
      int wrong = 0;
      while (wrong < 3) {
         int result = play(console, rand); // play one game
         if (result == 0) {
            wrong++;
         } else {
            points++;
         }
      }
      System.out.println("You earned " + points + " total points.");
   }

   // Builds one addition problem and presents it to the user.
   // Returns 1 point if you get it right, 0 if wrong.
   public static int play(Scanner console, Random rand) {
      // print the operands being added, and sum them
      int operands = rand.nextInt(4) + 2;
      int sum = rand.nextInt(10) + 1;
      System.out.print(sum);
      for (int i = 2; i <= operands; i++) {
         int n = rand.nextInt(10) + 1;
         sum += n;
         System.out.print(" + " + n);
      }
      System.out.print(" = ");
      
      // read user's guess and report whether it was correct
      int guess = console.nextInt();
      if (guess == sum) {
         return 1;
      } else {
         System.out.println("Wrong! The answer was " + total);
         return 0;
      }
   }
}