#include <cstdio>
#include <cstdlib>
#include <iostream>
#include <string>
#include <cmath>
#include <algorithm>
#include <vector>
#include <queue>
#include <stack>
#include <map>
#include <set>
#include <cstring>

typedef long long ll;
using namespace std;

#define mod 1000000007
#define INF 1000000000 //(int)1e9
#define LLINF 2000000000000000000 //(ll)2e18
#define PI  3.1415926536

#define SIZE 100000

int main(){
    int x,y,r;
    
    scanf("%d%d%d",&x,&y,&r);
    
    
    printf("%d\n",abs(x)+abs(y)+(int)ceil(r/0.70710678));
    
    
    return 0;
}