How to random more than one math problems' operators and check the correct answer in java

Question

import java.io.*;
public class AssignmentMT {

public static void main(String[] args) throws IOException{
    // TODO Auto-generated method stub
BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
    int number1, number2, number3, number4, number5;
    double answer;
    double geanswer = 0;
    String word;
    String operator = "";
    int score=0, totalscore=10;
    float percentage;
    int intoperator;

    word = br.readLine();


//Game Enhancement.
while (word.equals("Game Enhancement")){
    System.out.println("Now you are in the game enhancement, be ready for your 4 level qustions. Write your answer after press enter.");
    System.out.println("Press 'Go' to start!");
    word = br.readLine();
while (!word.equals("Go")){
    System .out.println("Please enter again.");
    word = br.readLine();
}
while (word.equals("Go")){

    System.out.println("-Level 1-");
        number1 = (int) (Math.round (Math.random () * 9)+1);    
        number2 = (int) (Math.round (Math.random () * 9)+1);
        intoperator = (int) (Math.round (Math.random () * 4)+1);
        switch (intoperator) {
        case 1:
            operator = "+";
            geanswer = number1+number2; 
        break;
        case 2:
            operator = "-";
            geanswer = number1-number2; 
        break;
        case 3:
            operator = "×";
            geanswer = number1*number2;
        break;
        case 4:
            operator = "÷";
            geanswer = (double)Math.round(((double)number1/(double)number2)*100)/100;
        break;
        default:
            operator = "+";
            geanswer = number1+number2;
        break;
        }
    System.out.println( number1 + operator + number2 + "=");
    answer = Double.parseDouble(br.readLine());   
if(answer==geanswer){
    score++;
    }
    System.out.println("Your Score: " + score);


    System.out.println("-Level 2-");
    for (int i=1;i<=2;i++){
        number1 = (int) (Math.round (Math.random () * 9)+1);    
        number2 = (int) (Math.round (Math.random () * 9)+1);
        number3 = (int) (Math.round (Math.random () * 9)+1);
        intoperator = (int) (Math.round (Math.random () * 4)+1);
        switch (intoperator) {
        case 1:
            operator = "+";
            geanswer = number1+number2+number3; 
        break;
        case 2:
            operator = "-";
            geanswer = number1-number2-number3; 
        break;
        case 3:
            operator = "×";
            geanswer = number1*number2*number3;
        break;
        case 4:
            operator = "÷";
            geanswer = (double)Math.round(((double)number1/(double)number2/(double)number3)*100)/100;
        break;
        default:
            operator = "+";
            geanswer = number1+number2+number3;
        break;
        }
    System.out.println( number1 + operator + number2 + operator + number3 + "=");   
    answer = Double.parseDouble(br.readLine());
if(answer == geanswer){
    score++;
    }    
        }
    System.out.println("Your Score: " + score);


    System.out.println("-Level 3-");
    for (int i=1;i<=3;i++){
        number1 = (int) (Math.round (Math.random () * 9)+1);    
        number2 = (int) (Math.round (Math.random () * 9)+1);
        number3 = (int) (Math.round (Math.random () * 9)+1);
        number4 = (int) (Math.round (Math.random () * 9)+1);
        intoperator = (int) (Math.round (Math.random () * 4)+1);
        switch (intoperator) {
        case 1:
            operator = "+";
            geanswer = number1+number2+number3+number4; 
        break;
        case 2:
            operator = "-";
            geanswer = number1-number2-number3-number4; 
        break;
        case 3:
            operator = "×";
            geanswer = number1*number2*number3*number4;
        break;
        case 4:
            operator = "÷";
            geanswer = (double)Math.round(((double)number1/(double)number2/(double)number3/(double)number4)*100)/100;
        break;
        default:
            operator = "+";
            geanswer = number1+number2+number3+number4;
        break;
        }
    System.out.println( number1 + operator + number2 + operator + number3 + operator + number4 + "=");
    answer = Double.parseDouble(br.readLine());
if(answer == geanswer){
    score++;
    }    
        }
    System.out.println("Your Score: " + score); 



    System.out.println("-Level 4-");
    for (int i=1;i<=4;i++){
        number1 = (int) (Math.round (Math.random () * 9)+1);    
        number2 = (int) (Math.round (Math.random () * 9)+1);
        number3 = (int) (Math.round (Math.random () * 9)+1);
        number4 = (int) (Math.round (Math.random () * 9)+1);
        number5 = (int) (Math.round (Math.random () * 9)+1);
        intoperator = (int) (Math.round (Math.random () * 4)+1);
        switch (intoperator) {
        case 1:
            operator = "+";
            geanswer = number1+number2+number3+number4+number5; 
        break;
        case 2:
            operator = "-";
            geanswer = number1-number2-number3-number4-number5; 
        break;
        case 3:
            operator = "×";
            geanswer = number1*number2*number3*number4*number5;
        break;
        case 4:
            operator = "÷";
            geanswer = (double)Math.round(((double)number1/(double)number2/(double)number3/(double)number4/(double)number5)*100)/100;
        break;
        default:
            operator = "+";
            geanswer = number1+number2+number3+number4+number5;
        break;
        }
    System.out.println( number1 + operator + number2 + operator + number3 + operator + number4 + operator + number5 + "=");
    answer = Double.parseDouble(br.readLine());
if(answer == geanswer){
    score++;
    }    
        }
percentage = (float)((score*100)/totalscore);
System.out.println("Your total Score: " + score);
System.out.println(" ");
System.out.println("Your got " + percentage + "% mark! Congratulation!");
System.out.println("Please enter Quit to end.");
word = br.readLine();
if (word.equals("Quit")){
    System.out.println(" ");
    System.out.println("That's the end of the contest. Thank you!");
}
          }

   }
       }

        }

Hi guys, I am a high school student. Now I have Grade 11 Computer Science in school. The question is, as you see, the teacher is ask for a math contest procedure. He said we need to do at least 10 levels. Level 1 has one random operator. Level 2 has two random operators ...and so on. Also, every time the participants answer correct, he/she will get one score, which is mean I have to write something to check the correct answer. I know I need to use for loop to do the ten levels, the fact is I already tried but I can't.................I'm going crazy.

Plz help me..... Thanks for read it!!!

The first thing you need to do is *learn how to format your code*. What you have there is frankly just scary. — Luke Joshua Park, Mar 05 '16 at 20:23
@Shirley This is a really basic question (and a simple one if you break it down) Make sure you can generate 1 test question first. Once it's done, enclose it with a for loop. — user3437460, Mar 05 '16 at 20:24

score 0 · Accepted Answer · answered Mar 05 '16 at 20:31

You should break down the problem into the following:

For each level, you first need to generate the correct number of random integers on which you will perform the operations. (for level i, i+1 integers)
Next, you need to generate i operators for level i.

So essentially, you should be thinking about nested for loops, with internal loops depending on the current value of counter of outer loop. I hope this helps.

How to random more than one math problems' operators and check the correct answer in java

1 Answers1