#include <iostream>
#include <string>
#include <algorithm>
#include <vector>
#include <map>
#include <set>
#include <queue>
#include <cmath>
#include <numeric>
#include <utility>
#include <iomanip>

using namespace std;
using int64 = long long;

struct aaa{aaa(){cin.tie(nullptr); ios::sync_with_stdio(false); cout<<fixed<<setprecision(20);};}aaa;

int main() {
    int x, y, r;
    cin >> x >> y >> r;
    x = abs(x);
    y = abs(y);
    cout << x + y + (int)(r*sqrt(2)+1) << endl;
}