#include <bits/stdc++.h>
using namespace std;
//#define int long long
typedef long long ll;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define pb push_back
#define S second
#define F first
#define all(x) (x).begin(),(x).end()
#define migmig ios::sync_with_stdio(0);cin.tie(0);cout.tie(0);
#define lc id << 1
#define rc lc|1
#define mid ((l + r)/2)
const int maxn = 3e5 + 10;
//const int maxk = 101;
const int mod = 998244353;
const int inf = 1e9 + 1;
const int LOG = 21;
int n, k, a[maxn], b[maxn], t[maxn], f[maxn], mx[maxn * 4];
map<int, int> lst;
vector<int> kl, seg[maxn * 4];
void build_f(int id = 1, int l = 0, int r = kl.size()) {
if (l + 1 == r) {
mx[id] = lst[kl[l]];
return;
}
build_f(lc, l, mid);
build_f(rc, mid, r);
mx[id] = max(mx[lc], mx[rc]);
}
int get_mx(int ql, int qr, int id = 1, int l = 0, int r = kl.size()) {
// if (l == r)
// return 0;
if (r <= ql || qr <= l)
return 0;
if (ql <= l && r <= qr)
return mx[id];
return max(get_mx(ql, qr, lc, l, mid), get_mx(ql, qr, rc, mid, r));
}
vector<int> merge(vector<int> A, vector<int> B) {
vector<int> ret;
int i = 0, j = 0;
while (i < A.size() && j < B.size()) {
if (A[i] <= B[j]) {
ret.pb(A[i]);
i++;
}
else {
ret.pb(B[j]);
j++;
}
}
while (i < A.size()) {
ret.pb(A[i]);
i++;
}
while (j < B.size()) {
ret.pb(B[j]);
j++;
}
return ret;
}
void build(int id = 1, int l = 1, int r = k + 1) {
if (l + 1 == r) {
seg[id].pb(t[l]);
return;
}
build(lc, l, mid);
build(rc, mid, r);
seg[id] = merge(seg[lc], seg[rc]);
}
int get(int ql, int qr, int x, int id = 1, int l = 1, int r = k + 1) {
if (r <= ql || qr <= l)
return 0;
if (ql <= l && r <= qr) {
int cnt = lower_bound(all(seg[id]), x - 1) - seg[id].begin();
return (seg[id].size() - cnt);
}
return (get(ql, qr, x, lc, l, mid) + get(ql, qr, x, rc, mid, r));
}
signed main() {
cin >> n >> k;
for (int i = 1; i <= n; i++) {
cin >> a[i] >> b[i];
lst[a[i]] = 0;
lst[b[i]] = 0;
kl.pb(a[i]);
kl.pb(b[i]);
}
for (int i = 1; i <= k; i++) {
cin >> t[i];
lst[t[i]] = i;
kl.pb(t[i]);
}
sort(all(kl));
kl.erase(unique(all(kl)), kl.end());
// for (int x : kl)
// cout << x << ' ';
// cout << '\n';
build_f();
for (int i = 1; i <= n; i++) {
int l = lower_bound(all(kl), a[i]) - kl.begin();
int r = lower_bound(all(kl), b[i]) - kl.begin();
if (l > r)
swap(l, r);
f[i] = get_mx(l, r);
// cout << i << ' ' << f[i] << '\n';
}
build();
ll ans = 0;
for (int i = 1; i <= n; i++) {
int cnt = get(f[i] + 1, k + 1, max(a[i], b[i]));
if (f[i] != 0) {
if (a[i] > b[i])
swap(a[i], b[i]);
if (cnt % 2 == 0)
ans += b[i];
else
ans += a[i];
}
else {
if (cnt % 2 == 0)
ans += a[i];
else
ans += b[i];
}
}
cout << ans << '\n';
}
