#include <algorithm>
#include <array>
#include <cmath>
#include <cstdio>
#include <iostream>
#include <numeric>
#include <optional>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

int main() {
    int32_t x, y, r;
    cin >> x >> y >> r;
    x = abs(x);
    y = abs(y);
    r = (int32_t)ceil(sqrt(2) * r);
    cout << x + y + r << endl;
    return 0;
}