#include <iostream>
#include <cmath>

using namespace std;

int main() {
    int x, y, r;
    cin >> x >> y >> r;
    //double ufo_dist = pow((x*x+y*y), 0.5) + r;
    double ufo_dist = abs(x)+abs(y)+pow(2.0, 0.5)*r;
    double kekkai_dist=0;
    int n=0;
    for(;n <=ufo_dist;n++);

    cout << n << endl;
}