Problem:
Score : 100 points

Problem Statement

We have a sandglass that runs for X seconds. The sand drops from the upper bulb at a rate of 1 gram per second. That is, the upper bulb initially contains X grams of sand.

How many grams of sand will the upper bulb contains after t seconds?

Constraints

1≤X≤10^9

1≤t≤10^9

X and t are integers.

Input

The input is given from Standard Input in the following format:

X t

Output

Print the number of sand in the upper bulb after t second.

Sample Input 1

100 17

Sample Output 1

83

17 out of the initial 100 grams of sand will be consumed, resulting in 83 grams.

Sample Input 2

48 58

Sample Output 2

0

All 48 grams of sand will be gone, resulting in 0 grams.

Sample Input 3

1000000000 1000000000

Sample Output 3

0

Solution in Java8 (OpenJDK 1.8.0) (judge verdict: Accepted)

import java.util.Scanner;

/**
 * お遊び
 *
 * @author s-sugimoto
 */
public class Main {

	/**
	 * 隠蔽
	 */
	private Main() {
	}

	/**
	 * main
	 *
	 * @param args 起動引数
	 */
	public static void main(String[] args) {
		Scanner scanner = new Scanner(System.in);
		int num1 = scanner.nextInt();
		int num2 = scanner.nextInt();

		int output = getLogic(num1, num2);
		System.out.println(output);
	}

	/**
	 * ロジック群
	 */
	private static int getLogic(int num1, int num2) {
		if (num1 < num2) {
			return 0;
		}
		int result = num1 - num2;
		return result;
	}
}