#include<iostream>
#include<cstdio>
#include<cmath>
using namespace std;
#define maxn 200100
#define ll long long
ll read()
{
	ll x,f=1;
	char ch;
	while(ch=getchar(),!isdigit(ch))if(ch=='-')f=-1;
	x=ch-48;
	while(ch=getchar(),isdigit(ch))x=x*10+ch-48;
	return x*f;
}
void write(ll x)
{
	if(x<0)putchar('-'),x=-x;
	int cnt=0;char ch[50];
	while(ch[++cnt]=x%10+48,x/=10);
	while(putchar(ch[cnt]),--cnt);
	putchar('\n');
}
struct query 
{
	int l,r;
}b[maxn];
ll w[maxn],s[maxn],v[maxn],c[maxn];
int main()
{
	freopen("qc.in","r",stdin);
	freopen("qc.out","w",stdout);
	int n=read(),m=read();ll S=read(),l=1LL<<62,r=0,tot=0,ans=1LL<<62;
	for(int i=1;i<=n;i++)w[i]=read(),v[i]=read(),l=min(l,w[i]),r=max(r,w[i]);
	for(int i=1;i<=m;i++)b[i].l=read(),b[i].r=read();
	while(l<=r)
	{
		ll mid=(l+r)>>1;tot=0;
		for(int i=1;i<=n;i++)
		{
			s[i]=s[i-1];c[i]=c[i-1];
			if(w[i]>=mid)s[i]++,c[i]+=v[i];
		}
		for(int i=1;i<=m;i++)
			tot+=(s[b[i].r]-s[b[i].l-1])*(c[b[i].r]-c[b[i].l-1]);
		if(tot<=S)r=mid-1;
		else l=mid+1;
		ans=min(ans,(ll)abs(S-tot));
	}
	write(ans);
	//system("pause");
}