#include <bits/stdc++.h>
using namespace std;
#define ff first
#define ss second
#define pb push_back
#define pf push_front
#define mp make_pair
#define ll long long
int movesdone[524288];
int maxseg[524288];
vector<int> moves(200000);
vector<pair<int,int>> cards(200000);
vector<pair<int,int>> moveindex;
void maxupdate(int pos, int val) {
pos += 262144;
maxseg[pos] = val;
while (pos != 1) {
pos /= 2;
maxseg[pos] = max(maxseg[pos * 2 + 1], maxseg[pos * 2]);
}
}
int maxfind(int l, int r) {
l += 262144; r += 262144;
int val = 0;
while (l <= r) {
if (l % 2 == 1) val = max(val, maxseg[l++]);
if (r % 2 == 0) val = max(val, maxseg[r--]);
l /= 2; r /= 2;
}
return val;
}
void update(int pos) {
pos += 262144;
movesdone[pos] = 1;
while (pos != 1) {
pos /= 2;
movesdone[pos] = movesdone[pos * 2 + 1] + movesdone[pos * 2];
}
}
int find(int l, int r) {
l += 262144; r += 262144;
int val = 0;
while (l <= r) {
if (l % 2 == 1) val += movesdone[l++];
if (r % 2 == 0) val += movesdone[r--];
l /= 2; r /= 2;
}
return val;
}
bool comp(int a, int b) {
return max(cards[a].ff, cards[a].ss) > max(cards[b].ff, cards[b].ss);
}
int main() {
for (int i=0;i<524288;i++) {
movesdone[i] = 0;
maxseg[i] = 0;
}
int n, k; cin >> n >> k;
for (int i=0;i<n;i++) {
cin >> cards[i].ff >> cards[i].ss;
}
for (int i=0;i<k;i++) {
cin >> moves[i];
moveindex.pb(mp(moves[i], i));
maxupdate(i, moves[i]);
}
sort(moveindex.begin(), moveindex.end());
vector<int> queries(n);
vector<int> order;
for (int i=0;i<n;i++) {order.pb(i);}
sort(order.begin(), order.end(), comp);
int curmax = k;
for (int i: order) {
if (cards[i].ff == cards[i].ss) {
queries[i] = -1; continue;
}
while (curmax) {
if (moveindex[curmax - 1].ff >= max(cards[i].ff, cards[i].ss)) {
maxupdate(moveindex[curmax - 1].ss, 0);
curmax -= 1;
} else break;
}
int top = k, bottom = -1, mid;
while (top > bottom + 1) {
mid = (top + bottom) / 2;
if (maxfind(mid, k - 1) >= min(cards[i].ff, cards[i].ss)) {
bottom = mid;
} else {
top = mid;
}
}
queries[i] = bottom;
}
//for (int i=0;i<n;i++) {
// cout << order[i] << ' ' << queries[order[i]] << '\n';
//}
ll ans = 0;
curmax = k;
for (int i: order) {
while (curmax) {
if (moveindex[curmax - 1].ff >= max(cards[i].ff, cards[i].ss)) {
update(moveindex[curmax - 1].ss);
curmax -= 1;
} else break;
}
int flips = find(queries[i] + 1, k - 1);
//cout << i << ' ' << flips << '\n';
if (queries[i] == -1) {
if (flips % 2 == 1) ans += cards[i].ss;
else ans += cards[i].ff;
} else if (cards[i].ff > cards[i].ss) {
if (flips % 2 == 1) ans += cards[i].ss;
else ans += cards[i].ff;
} else {
if (flips % 2 == 1) ans += cards[i].ff;
else ans += cards[i].ss;
}
}
cout << ans;
}
