#include<bits/stdc++.h>
using namespace std;
typedef long long ll;
const int N = 2e5+10;
ll n, m, s;
ll ans = 1e18;
ll sum[N], sumv[N];
struct Ore{
	ll w, v;
}A[N], B[N];
bool check(ll W){
	memset(sum, 0, sizeof sum);
	memset(sumv, 0, sizeof sumv);
	for (int i = 1; i <= n; i ++){
		if(A[i].w >= W){
			sum[i] = sum[i-1] + 1;
			sumv[i] = sumv[i-1] + A[i].v;
		}else{
			sum[i] = sum[i-1];
			sumv[i] = sumv[i-1];
		}
	}
	ll cnt = 0;
	for (int i = 1; i <= m; i ++){
		ll l = B[i].w, r = B[i].v;
		cnt += (sum[r]-sum[l-1]) * (sumv[r]-sumv[l-1]);
	}
	ans = min(ans, abs(s-cnt));
	return cnt >= s;
}
int main(){
	cin >> n >> m >> s;
	for (int i = 1; i <= n; i ++) cin >> A[i].w >> A[i].v;
	for (int i = 1; i <= m; i ++) cin >> B[i].w >> B[i].v;
	ll l = 0, r = 1e6+2;
	while(l < r){
		ll mid = l + r + 1>> 1;
		if(check(mid)) l = mid;
		else r = mid - 1;
	}
	cout << ans;
	return 0;
}