Thread: Unable to execute the program (no compilation error)

Dear experts,

I am doing my assignment on finding how many numbers in N digit satisfy K requirement.
However, when i am testing the code, i could compile it but i couldn't execute it.
I am wondering if i made mistake in the

x = result + y; // add them together and return it.

as when i comment this out, my program is able to execute,though i didn't get the right output value
Please kindly enlighten me.

Logic of my codes (example):

N = 15, K = 3

When N = 1, result = 0 + (N%10)
= 0 + (1%10)
= 1

y = N/10
= 1/10
= 0

x = 1 + 0
= 1
return x = 1

if (sumOfDigits(1) == K)
noOfNoSatisfy ++;
----------------------------------------------------
In the case of above, noOfSatisfy still remains as 0
-----------------------------------------------------
When N = 12, result = 0 + (N%10)
= 0 + (12%10)
= 2

y = N/10
= 12/10
= 1

x = 1 + 2
= 3
return x = 3

if (sumOfDigits(3) == K)
noOfNoSatisfy ++;

----------------------------------------------------
In the case of above, noOfSatisfy increase and plus 1
-----------------------------------------------------

import java.util.*;
 
public class Digits {
 
    public static int sumOfDigits(int x) {
        int result =0;
        int y =0;
        //eg. Let x be 1
        while(x>0){
			// eg. 1 = 1 + (1%10);
			result = result + (x%10); //take the last digit of x
			// eg. 0 = 1/10
			y = x/10; //take the first digit of x
			// eg. 1 = 1 + 0
                        x = result + y; // add them together and return it.
        }
        //eg. return 1
        return x;
 
    }
 
    public static void main(String[] args) {		
        int N, K, noOfNoSatisfy;
 
        Scanner sc = new Scanner (System.in);
 
		//eg. Let N be 1
        N = sc.nextInt();//indicate Number
		//eg. Let K be 1
        K = sc.nextInt();//indicate requirement number
 
        noOfNoSatisfy = 0; // to count how many time it matches with K (requirement number)
 
        for (int i = 1; i <=N; i++){
            if(sumOfDigits(i) == K){//eg. 1 == K
                noOfNoSatisfy ++; // plus 1 to count
            }
        } System.out.println(noOfNoSatisfy); //print the number of count
    }
}

Hello Alexie91,

I don't see where x would ever be less than 0 and thus you have an infinite loop. If the condition x>0 was to check if N was positive then I would suggest doing that before you even get to the loop. Really, this whole thing doesn't make much sense to me, if you can explain a little more about the assignment that may help.