Problem:
Score : 100 points

Problem Statement

You went shopping to buy cakes and donuts with X yen (the currency of Japan).

First, you bought one cake for A yen at a cake shop.
Then, you bought as many donuts as possible for B yen each, at a donut shop.

How much do you have left after shopping?

Constraints

1 \leq A, B \leq 1 000

A + B \leq X \leq 10 000

X, A and B are integers.

Input

Input is given from Standard Input in the following format:

X
A
B

Output

Print the amount you have left after shopping.

Sample Input 1

1234
150
100

Sample Output 1

84

You have 1234 - 150 = 1084 yen left after buying a cake.
With this amount, you can buy 10 donuts, after which you have 84 yen left.

Sample Input 2

1000
108
108

Sample Output 2

28

Sample Input 3

579
123
456

Sample Output 3

0

Sample Input 4

7477
549
593

Sample Output 4

405

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Runtime Error)

import java.util.Scanner;

public class Main
{
    public static void main(String[] args)
    {
        int a,b,c,x;
        int output=0;
        int i,j,k;

        Scanner scan = new Scanner(System.in);
        a=scan.nextInt();
        b=scan.nextInt();
        c=scan.nextInt();
        x=scan.nextInt();

        for(i=0;i<=a;i++)
        {
            for(j=0;j<=b;j++)
            {
                for(k=0;k<=c;k++)
                {
                    if(500*i+100*j+k*50==x)
                    {
                        output++;
                    }
                }
            }
        }
        System.out.println(output);
    } 
}