#include <iostream> #include <fstream> #include <typeinfo> #include <vector> #include <stack> #include <cmath> #include <set> #include <map> #include <string> #include <algorithm> #include <cstdio> #include <queue> #include <iomanip> #include <cctype> #define syosu(x) fixed<<setprecision(x) using namespace std; typedef long long ll; typedef unsigned long long ull; typedef pair<int,int> P; typedef pair<double,double> pdd; typedef pair<ll,ll> pll; typedef vector<int> vi; typedef vector<vi> vvi; typedef vector<double> vd; typedef vector<vd> vvd; typedef vector<ll> vl; typedef vector<vl> vvl; typedef vector<char> vc; typedef vector<vc> vvc; typedef vector<string> vs; typedef vector<bool> vb; typedef vector<vb> vvb; typedef vector<P> vp; typedef vector<vp> vvp; typedef vector<pll> vpll; typedef pair<int,P> pip; typedef vector<pip> vip; const int inf=1<<30; const ll INF=1ll<<52; const double pi=acos(-1); const double eps=1e-8; const ll mod=1e9+7; const vi emp; const int dx[4]={0,1,0,-1},dy[4]={1,0,-1,-0}; const int DX[8]={-1,-1,-1,0,0,1,1,1},DY[8]={1,0,-1,1,-1,1,0,-1}; double x,y,r; int main(){ cin>>x>>y>>r; cout<<ceil(abs(x)+abs(y)+sqrt(2)*r)<<endl; }