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 C++ (GCC 9.2.1) (judge verdict: Wrong Answer)

// lcmとか__builtin_popcountとかはg++ -std=c++17 default.cppみたいなかんじで

#include <bits/stdc++.h>
#define mod 1000000007
#define INF LLONG_MAX
#define ll long long
#define ln cout<<endl
#define Yes cout<<"Yes"<<endl
#define NO cout<<"NO"<<endl
#define YES cout<<"YES"<<endl
#define No cout<<"No"<<endl
#define REP(i,m,n) for(ll i=(ll)(m);i<(ll)(n);i++)
#define rep(i,n) REP(i,0,n)
#define all(x) (x).begin(),(x).end()
#define rall(x) (x).rbegin(),(x).rend()
using namespace std;
ll dx[4]={1,0,-1,0};
ll dy[4]={0,1,0,-1};

int main() {
    cin.tie(0);
   	ios::sync_with_stdio(false);

    ll  a,b,c,d,e,n,k,maxi=0,f=0,mini=INF,sum=0,q;
	string str,g,ko;
    ll x,y,w;
    char hoge;
    cin>>w>>a>>b;
    ll al,bl;
    al=a+w;
    bl=b+w;
    if(a<=bl||b<al) cout<<0<<endl;
    else {
        cout<<min(abs(b-al),abs(a-bl));
    }
    return 0;
}