#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const ll MN = 200005;
struct pii{ll f, s, l;}a[MN];
ll st[3*MN], q[MN], N, K, M, i, j, n, bit[MN];
long long ans; map<int,int> p;
bool cmp(pii i,pii j){return(i.l<j.l);}
ll qu(ll p){ll r=0;for(;p>0;p-=p&(-p))r+=bit[p]; return r;}
void up(ll p){for(;p<=M;p+=p&(-p))bit[p]++;}
void upd(ll i,ll s,ll e,ll ind, ll k){
if(s != e){
if((s+e)/2 < ind) upd(2*i+1,(s+e)/2+1,e,ind,k);
else upd(2*i,s,(s+e)/2,ind,k);
st[i] = max(st[2*i],st[2*i+1]);
}
else st[i] = k;
}
ll rmq(ll i,ll s,ll e,ll ss,ll se){
if(ss > se) return -1;
if(s >= ss && e <= se) return st[i];
else if((s+e)/2 < ss) return rmq(2*i+1,(s+e)/2+1,e,ss,se);
else if((s+e)/2 >= se) return rmq(2*i,s,(s+e)/2,ss,se);
else return max(rmq(2*i+1,(s+e)/2+1,e,ss,se),rmq(2*i,s,(s+e)/2,ss,se));
}
int main(){
for(scanf("%lld%lld",&N,&K),i=1;i<=N;i++)
scanf("%lld%lld",&a[i].f,&a[i].s);
for(i=1;i<=K;i++){
scanf("%lld",&q[i]);
p[q[i]]=0;
}
for(auto v=p.begin();v!=p.end();v++) v->second = ++n;
M = p.size();
for(i=1;i<=K;i++)
upd(1,1,M,p[q[i]],i);
for(i=1;i<=N;i++){
ll l, r;
auto it = p.lower_bound(max(a[i].f,a[i].s)); --it;
r = (it==p.end())? -1:it->second;
it = p.lower_bound(min(a[i].f,a[i].s));
l = (it==p.end())? 1<<30:it->second;
a[i].l = rmq(1,1,M,l,r);
}
sort(a+1, a+N+1, cmp);
for(i=N,j=K;i>=1&&a[i].l!=-1;i--){
while(j>a[i].l){up(p[q[j]]);j--;}
if(a[i].f < a[i].s) swap(a[i].f,a[i].s);
auto tmp = p.lower_bound(a[i].f);
ll ind = (tmp==p.end())? M:tmp->second-1;
ll t = (qu(M)-qu(ind))%2;
ans += (t)? a[i].s : a[i].f;
}
while(j > 0){up(p[q[j]]); j--;}
for(;i>=1;i--){
auto tmp = p.lower_bound(max(a[i].s,a[i].f));
ll ind = (tmp==p.end())? M:tmp->second-1;
ll t = (qu(M)-qu(ind))%2;
ans += (t)? a[i].s : a[i].f;
}
printf("%lld\n",ans);
return 0;
}
