#define _USE_MATH_DEFINES
#include<stdio.h>
#include<string>
#include<iostream>
#include<cctype>
#include<cstdio>
#include<vector>
#include<stack>
#include <algorithm>
#include<math.h>
#include<set>
#include<map>
#include<iomanip>
//#include<bits/stdc++.h>


using namespace std;

int main(){
	int x,y,p;
	cin>>x>>y>>p;
	int a=0;
	a+=abs(x/p)+abs(y/p);
	if(x%p)a++;
	if(y%p)a++;
	if(y<0)a+=2;
	if(y>0&&x)a++;
	
	cout<<a<<endl;

	return 0;
}