#include<stdio.h>
#include<algorithm>
#include<math.h>
#define N 200005
using namespace std;
long long w[N],v[N],l[N],r[N],qn[N],qv[N],sum;
long long n,m,s,W=0,maxx;
bool check(long long mid)
{
	int y=0;
	for(int i=1;i<=N-1;i++)
	{
		qn[i]=0;
		qv[i]=0;
	}
	for(int i=1;i<=n;i++)
	{
		if(w[i]>=mid)
		{
			qn[i]=qn[i-1]+1;
			qv[i]=qv[i-1]+v[i];
		}
		else
		{
			qn[i]=qn[i-1];
			qv[i]=qv[i-1];
		}
	}
	for(int i=1;i<=m;i++)
	{
		y=y+(qn[r[i]]-qn[l[i]-1])*(qv[r[i]]-qv[l[i]-1]);
	}
	sum=abs(y-s);
	if(y>s)
	return 1;
	return 0;
	
}
int main()
{
	scanf("%lld%lld%lld",&n,&m,&s);
	for(int i=1;i<=n;i++)
	{
		scanf("%lld%lld",&w[i],&v[i]);
		maxx=max(maxx,w[i]);
	}
	for(int i=1;i<=m;i++)
	{
		scanf("%lld%lld",&l[i],&r[i]);
	}
	long long ans=2e18;
	long long low=0;
	long long high=maxx+2;
	while(low<=high)
	{
		long long mid=(low+high)/2;
		if(check(mid))
		{
			low=mid+1;
			W=mid;
		}
		else
		{
			high=mid-1;
		}
		ans=min(sum,ans);
	}
	printf("%lld",ans);
	return 0;
}