#include<bits/stdc++.h>
#define pb(a) push_back(a)
#define mp(a,b) make_pair(a,b)
#define int long long
#define mod (1000000007)
// int mod;
#ifndef ONLINE_JUDGE
#pragma GCC optimize(2)
#endif
using namespace std;
namespace IO{
	inline int read(){
		int n=0;
		int s=1;
		char x;
		while((x=getchar())<'0'||x>'9')
			if(x=='-')
				s=-1;
		while(x>='0'&&x<='9'){
			n=(n<<1)+(n<<3)+(x^48),
			x=getchar();
		}
		return n*s;
	}
	void write(char x){
		putchar(x);
	}
	void write(const char *x){
		for(;*x;++x)
			putchar(*x);
	}
	void write(char *x){
		for(;*x;++x)
			putchar(*x);
	}
	void write(signed x){
		if(x<0)putchar('-'),x=-x;
		if(x>9)write(x/10);
		putchar('0'+x-x/10*10);
	}
	void write(long long x){
		if(x<0)putchar('-'),x=-x;
		if(x>9)write(x/10);
		putchar('0'+x-x/10*10);
	}
	void write(double x){
		printf("%lf",x);
	}
	template<typename type1,typename type2,typename ...typen>
	void write(type1 a1,type2 a2,typen ...an){
		write(a1);
		write(a2,an...);
	}
}// namespace IO
inline long long max(long long a,long long b){return a>b?a:b;}
inline long long min(long long a,long long b){return a>b?b:a;}
inline signed max(signed a,signed b){return a>b?a:b;}
inline signed min(signed a,signed b){return a>b?b:a;}
// stop
struct Node{
	int l,r;
	bool operator<(Node x)const{
		return l<x.l;
	}
}cl1[300001],cl2[300001];
map<int,int>mem[300001][2];
// #define wtf
signed main(){
	using namespace IO;
	// define int long long
	// mod = 1000000007
	#ifdef wtf
	string filename="name";
	freopen((filename+".in").c_str(),"r",stdin);
	freopen((filename+".out").c_str(),"w",stdout);
	#endif
	int n=read()+1,m=read(),k=read();
	cl1[1].l=0,cl1[1].r=1;
	for(int i=2;i<=n;i++){
		cl1[i].l=read(),cl1[i].r=read();
	}
	sort(cl1+1,cl1+n+1);
	for(int i=1;i<=m;i++){
		cl2[i].l=read(),cl2[i].r=read();
	}
	sort(cl2+1,cl2+m+1);
	int pos1=1,pos2=1;
	int ans=-1;
	mem[1][0][0]=0;
	for(int i=1,j=1;i<=n||j<=m;){
		if(j>m||(i<=n&&cl1[i].l<=cl2[j].l)){
			int maxm=-1;
			for(auto x:mem[i][0]){
				// cout<<0<<" "<<x.first<<" "<<x.second<<"\n";
				assert(x.first<cl1[i].r);
				maxm=max(maxm,x.second);
				while(pos2<=m&&cl2[pos2].r<=x.first+k)pos2++;
				if(pos2>m)continue;
				int t=max(cl2[pos2].l,x.first+k);
				if(t>=cl2[pos2].r)assert(0);
				mem[pos2][1][t]=max(mem[pos2][1][t],x.second+1);
			}
			ans=max(ans,maxm);
			if(maxm!=-1&&i<n)mem[i+1][0][cl1[i+1].l]=max(mem[i+1][0][cl1[i+1].l],maxm+1);
			i++;
			pos1=max(pos1,i);
		}
		else {
			int maxm=-1;
			for(auto x:mem[j][1]){
				assert(x.first<cl2[j].r);
				// cout<<1<<" "<<x.first<<" "<<x.second<<"\n";
				maxm=max(maxm,x.second);
				while(pos1<=n&&cl1[pos1].r<=x.first+k)pos1++;
				if(pos1>n)continue;
				int t=max(cl1[pos1].l,x.first+k);
				if(t>=cl1[pos1].r)assert(0);
				mem[pos1][0][t]=max(mem[pos1][0][t],x.second+1);
			}
			ans=max(maxm,ans);
			if(maxm!=-1&&j<m)mem[j+1][1][cl2[j+1].l]=max(mem[j+1][1][cl2[j+1].l],maxm+1);
			j++;
			pos2=max(pos2,j);
		}
	}
	write(ans);
	return 0;
}
/*
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                          ----
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                  ----
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     ----

                     ----   ----

                     ----   ----

    ----   ----

    ----   ----

----------------------------------------
*/