#include<iostream>
#include<algorithm>
#include<vector>
#include<string>
#include<utility>
#include<map>
#include<set>
#include<queue>
#include<stack>
#include<functional>
#include<math.h>
#include<random>
#include <bitset>
using namespace std;
#define N (1000000000+7)
//#define N 998244353
#define INF 1e16
typedef long long ll;
typedef pair<int,int> P;
typedef pair<int,P> Q;
 
const int inf = (int)1e9; 
 
ll gcd(ll a, ll b) {
	if (b > a) {
		ll tmp = b;
		b = a;
		a = tmp;
	}
	if (a%b == 0)return b;
	else return gcd(b, a%b);
}


int main(void){
	ll X,Y,L;
	cin>>X>>Y>>L;
	if(X==0){
		if(Y==0)cout<<0<<endl;
		else{
			if(Y>0){
				if(Y%L==0)cout<<Y/L<<endl;
				else cout<<Y/L+1<<endl;
			}
			else{
				Y*=-1;
				if(Y%L==0)cout<<Y/L+2<<endl;
				else cout<<Y/L+3<<endl;
			}
		}
		return 0;
	}
	if(Y==0){
		if(X>0){
			if(X%L==0)cout<<X/L+1<<endl;
			else cout<<X/L+2<<endl;
		}
		else{
			X*=-1;
			if(X%L==0)cout<<X/L+1<<endl;
			else cout<<X/L+2<<endl;
		}
		return 0;
	}
	if(X>0&&Y>0){
		ll t1 = X/L+((X%L==0)?0:1);
		ll t2 = Y/L+((Y%L==0)?0:1);
		cout<<t1+t2+1<<endl;
		return 0;
	}
	if(X>0&&Y<0){
		Y*=-1;
		ll t1 = X/L+((X%L==0)?0:1);
		ll t2 = Y/L+((Y%L==0)?0:1);
		cout<<t1+t2+2<<endl;
		return 0;
	}
	if(X<0&&Y>0){
		X*=-1;
		ll t1 = X/L+((X%L==0)?0:1);
		ll t2 = Y/L+((Y%L==0)?0:1);
		cout<<t1+t2+1<<endl;
		return 0;
	}
	if(X<0&&Y<0){
		X*=-1;
		Y*=-1;
		ll t1 = X/L+((X%L==0)?0:1);
		ll t2 = Y/L+((Y%L==0)?0:1);
		cout<<t1+t2+2<<endl;
		return 0;
	}
	return 0;
}