#include using namespace std; typedef long long ll; typedef unsigned long long ull; typedef long double ld; #define FOR(i, a, b) for (int i=a; i<(b); i++) #define range(a) a.begin(), a.end() #define endl "\n" #define Yes() cout << "Yes" << endl #define No() cout << "No" << endl #define MP make_pair const unsigned long long mod = 1e9 + 7; const long long INF = 1LL<<60; const int dx[4]={1,0,-1,0}; const int dy[4]={0,1,0,-1}; void chmin(long long &a, long long b) { if (a > b) a = b; } void chmax(long long &a, long long b) { if (a < b) a = b; } int main(void){ ios::sync_with_stdio(0); cin.tie(0); int x, y, L, dir=0; cin >> x >> y >> L; if(y<0){ dir = 2; } x = abs(x); y = abs(y); if(x==0&&y==0){ cout << 0 << endl; }else if(x==0){ cout << (y - 1) / L + 1 + dir << endl; }else if(y==0){ cout << (x - 1) / L + 2<< endl; }else{ cout << (x - 1) / L + (y - 1) / L + 2 + dir << endl; } return 0; }