#include <iostream>
#include <cmath>
using namespace std;
int main(){
	int a,b,s;	cin>>a>>b>>s;
	if(abs(a-s)<=abs(b-s)){
		cout<<abs(a-s)+s<<endl;
	}
	else{
		if(a==0) a=2;
		cout<<abs(b-s)+s-1+a<<endl;
	}
	return 0;
}