#include <bits/stdc++.h>
#define endl '\n'
#define ll long long
using namespace std;
const int N = 2e5 + 10;
int n, m;
ll s;
struct node{
	ll w, v;
}a[N];
int l[N], r[N];
ll ans = LLONG_MAX;
ll sum1[N], sum2[N];
ll Y(ll x)
{
	ll sum = 0;
	memset(sum1, 0ll, sizeof(sum1));
	memset(sum2, 0ll, sizeof(sum2));
	for (int i = 1; i <= n; i++)
	{
		sum1[i] = sum1[i - 1] + (ll)(a[i].w >= x);
		sum2[i] = sum2[i - 1] + ((ll)(a[i].w >= x) * a[i].v);
	}
	for (int i = 1; i <= m; i++)
	{
		sum += (sum1[r[i]] - sum1[l[i] - 1]) * (sum2[r[i]] - sum2[l[i] - 1]);
	}
	return llabs(sum - s);
}
int main()
{
	//freopen("qc.in","r",stdin);
	//freopen("qc.out","w",stdout);
	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 >> l[i] >> r[i];
	}
	ll l = 0, r = 1e18;
	while (l <= r)
	{
		ll mid = (l + r) / 2;
		ll y = Y(mid);
		if (y > s)
		{
			l = mid + 1;
		}
		else
		{
			r = mid - 1;
		}
		ans = min(ans, y);
	}
	cout << ans;
	return 0;
}