#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <set>
#include <map>
#include <cmath>
#include <iomanip>
#include <codecvt>
#include <locale>
using namespace std;
using ll = long long;

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