1 #include<cstdio>
 2 #include<iostream>
 3 using namespace std;
 4 #define ll long long
 5 const int M=200008;
 6 int n,m,i,h,t,k,mn,mx,mid,w[M],v[M],l[M],r[M];
 7 ll s,sum[M],num[M];
 8 
 9 ll abs(ll x) { return x>0?x:-x; }
10 
11 ll cal(int p)
12 {
13     int i; ll t=0;
14     for (i=1;i<=n;i++)
15         if (w[i]>=p) num[i]=num[i-1]+1,sum[i]=sum[i-1]+v[i];
16         else num[i]=num[i-1],sum[i]=sum[i-1];
17     for (i=1;i<=m;i++) t+=(num[r[i]]-num[l[i]-1])*(sum[r[i]]-sum[l[i]-1]);
18     return t;
19 }
20 
21 int main()
22 {
23     scanf("%d%d%lld",&n,&m,&s),mn=1000003;
24     for (i=1;i<=n;i++) scanf("%d%d",&w[i],&v[i]),mx=max(mx,w[i]),mn=min(mn,w[i]);
25     for (i=1;i<=m;i++) scanf("%d%d",&l[i],&r[i]);
26     for (h=mn,t=++mx;h<t;)
27     {
28         mid=h+t>>1;
29         if (cal(mid)>s) h=mid+1;
30         else t=mid,k=mid;
31     }
32     if (cal(h)-s<cal(k)-s) k=h;
33     printf("%lld\n",abs(min(s-cal(k),cal(k-1)-s)));
34     return 0;
35 }