Problem:
Score : 200 points

Problem Statement

AtCoDeer the deer found two rectangles lying on the table, each with height 1 and width W.
If we consider the surface of the desk as a two-dimensional plane, the first rectangle covers the vertical range of [0,1] and the horizontal range of [a,a+W], and the second rectangle covers the vertical range of [1,2] and the horizontal range of [b,b+W], as shown in the following figure:

AtCoDeer will move the second rectangle horizontally so that it connects with the first rectangle.
Find the minimum distance it needs to be moved.

Constraints

All input values are integers.

1≤W≤10^5

1≤a,b≤10^5

Input

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

W a b

Output

Print the minimum distance the second rectangle needs to be moved.

Sample Input 1

3 2 6

Sample Output 1

1

This input corresponds to the figure in the statement. In this case, the second rectangle should be moved to the left by a distance of 1.

Sample Input 2

3 1 3

Sample Output 2

0

The rectangles are already connected, and thus no move is needed.

Sample Input 3

5 10 1

Sample Output 3

4

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

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int W = sc.nextInt(),a=sc.nextInt(),b=sc.nextInt();

		if(a+W<b) {
			System.out.println(b-a-W);
		}else if(a>b+W){
			System.out.println(a-b-W);
		}else {
			System.out.println(0);
		}




	}
	public static int sample(int N,int M,char[][] arrayA,char[][] arrayB,int k) {
		int res=0;
		for(int i=0;i<N-M+1;i++) {
			for(int j=0;j<M;j++) {
				for(int l=0;l<M;l++) {
					if(arrayA[j+k][l+i]!=arrayB[j][l]) {
						res = 1;
						break;
					}
				}
			}
			if(res == 0) {
				return 0;
			}
			res = 0;
		}
		return 1;
	}

}