//khodaya khodet komak kon
#include <bits/stdc++.h>
#define F first
#define S second
#define pb push_back
#define all(x) x.begin(), x.end()
#pragma GCC optimise ("ofast")
#pragma GCC optimise("unroll-loops")
#define int long long
using namespace std;
typedef long long ll;
typedef pair<int, int> pii;
typedef vector<int> vi;
const int N = 200000 + 10;
const ll MOD = 1000000000 + 7;
const ll INF = 1000000000000000000;
const ll LOG = 25;
vector<int> seg[N << 2], T;
vector<pii> t;
int n, a[N], b[N], k, A[N], ans, aa[N], bb[N];
void build(int id, int l, int r){
if (r - l == 1){
seg[id].pb(A[l]);
return;
}
int md = (l + r) >> 1;
build(id << 1, l, md);
build(id << 1 | 1, md, r);
for (auto u:seg[id << 1]) seg[id].pb(u);
for (auto u:seg[id << 1 | 1]) seg[id].pb(u);
sort(all(seg[id]));
}
int get(int id, int lq, int rq, int l, int r){
if (rq <= l || r <= lq) return 0;
if (lq <= l && r <= rq){
return seg[id].back();
}
int md = (l + r) >> 1;
return max(get(id << 1, lq, rq, l, md), get(id << 1 | 1, lq, rq, md, r));
}
int Get(int id, int lq, int rq, int x, int l, int r){
if (rq <= l || r <= lq) return 0;
if (lq <= l && r <= rq){
int tt = lower_bound(all(seg[id]), x) - seg[id].begin();
return seg[id].size() - tt;
}
int md = (l + r) >> 1;
return (Get(id << 1, lq, rq, x, l, md) + Get(id << 1 | 1, lq, rq, x, md, r));
}
int32_t main(){
ios::sync_with_stdio(0); cin.tie(0); cout.tie(0);
cin >> n >> k;
for (int i = 1; i <= n; i++) {cin >> a[i] >> b[i]; aa[i] = a[i]; bb[i] = b[i];}
for (int i = 1; i <= k; i++){
int x;
cin >> x;
t.pb({x, i});
T.pb(x);
}
sort(all(t));
sort(all(T));
for (int i = 1; i <= n; i++){
int x = lower_bound(all(T), a[i]) - T.begin() + 1;
a[i] = x;
x = lower_bound(all(T), b[i]) - T.begin() + 1;
b[i] = x;
}
//cout << '\n';
for (int i = 1; i <= k; i++) A[i] = t[i - 1].S;
build(1, 1, N + 1);
for (int i = 1; i <= n; i++){
//cout << a[i] << ' ' << b[i] << '\n';
int x = get(1, min(a[i], b[i]), max(a[i], b[i]), 1, N + 1);
if (a[i] - b[i] == 0) x = 0;
int tt = Get(1, max(a[i], b[i]), k + 1, x, 1, N + 1);
//cout << x << '\n';
//cout << tt << '\n';
if (x == 0){
if (tt % 2 == 1) ans += bb[i];
else ans += aa[i];
continue;
}
if (tt % 2 == 1) ans += min(aa[i], bb[i]);
else ans += max(aa[i], bb[i]);
}
cout << ans;
return 0;
}
/*
1 6
2 5
1 2 6 4 5 1
*/
