#include<bits/stdc++.h>
#define rep(i,a,b) for(int i=int(a);i<int(b);++i)
using namespace std;
typedef long long ll;
int INF = (1LL << 30) - 1;
int MOD = 1e9+7;
main(){
    int A,B,S;
    cin >> A >> B >> S;
    if(S == 1){
        cout << (A == 0 ? 2 : A) << endl;
    //Aが移動する
    }else if(abs(S - A) <= abs(S - B)){
        cout << abs(S - A) + S << endl;
    }else{
        int a = abs(S - B) + abs(S - A) + A;
        int b = abs(S - B) + (S - 1) + abs(1 - A) + 1;
        if(A == 0)a += 1; 
        //cout << a << " " << b << endl;
        cout << min(a,b) << endl;
    }
}