#pragma GCC optimize("Ofast")
#pragma GCC optimize("unroll-loops")
#pragma GCC optimize("inline")
#include <bits/stdc++.h>
using namespace std;
#define kien long long
#define pb push_back
#define FOR(i, a, b) for (int i = a;i <= b; i++)
#define FORD(i, a, b) for (int i = a;i >= b; i--)
#define pii pair<int, int>
#define dembit(a) __builtin_popcountll(a)
#define task "a"
#define fin(x) freopen(x".inp","r",stdin)
#define fou(x) freopen(x".out","w",stdout)
#define debug(x) cout << x << " ";
#define down cout << "\n"
const kien MOD = 1e9 + 7;
const int NTEST = 100;
const int Million = 1e6 + 5;
const int MXN = 1e5 + 5;
mt19937 rd(chrono::high_resolution_clock::now().time_since_epoch().count());
kien rand(kien l, kien r) {
assert(l <= r);
return uniform_int_distribution<kien>(l, r)(rd);
}
kien n, k, m, dem, b[MXN + 5], u, v, a[1000000];
kien maxx, minn, vtr, l, r, ans, dp[MXN];
struct segment {
int st[4 * MXN], lazy[4 * MXN];
void build (int id, int l, int r) {
if (l == r) {
st[id] = a[l];
return;
}
int mid = (l + r) >> 1;
build (id << 1, l , mid);
build (id << 1 | 1, mid + 1, r);
st[id] = max(st[id << 1], st[id << 1 | 1]);
}
void push (int id) {
st[id << 1] += lazy[id];
st[id << 1 | 1] += lazy[id];
lazy[id << 1] += lazy[id];
lazy[id << 1 | 1] += lazy[id];
lazy[id] = 0;
}
void update (int id, int l, int r, int u, int v, int val) {
if (u > r or v < l) {
return;
}
if (u <= l and r <= v) {
st[id] += val;
lazy[id] += val;
return;
}
push(id);
int mid = (l + r) >> 1;
update (id << 1, l, mid, u, v, val);
update (id << 1 | 1, mid + 1, r, u ,v, val);
st[id] = st[id << 1] + st[id << 1 | 1];
}
kien get (int id, int l, int r, int pos) {
if (l == r) return st[id];
push(id);
int mid = (l + r) >> 1;
if (pos <= mid) return get(id << 1, l, mid, pos);
else return get(id << 1 | 1, mid + 1, r, pos);
}
} ST;
void solve() {
cin >> n >> k;
FOR (i, 1, n) {
cin >> a[i] >> b[i];
}
while (k--) {
cin >> r;
ST.update(1, 1, n, 1, r, 1);
}
FOR (i, 1, n) {
if (a[i] <= b[i]) {
int a1 = ST.get(1, 1, n, a[i]);
int b1 = ST.get(1, 1, n, b[i]);
if (a1 == b1) {
if (a1 % 2 == 0) ans += a[i]; else ans += b[i];
}
else if (a1 - b1 >= 2) ans += b[i];
else ans += a[i];
}
else {
int a2 = ST.get(1, 1, n, a[i]);
int b2 = ST.get(1, 1, n, b[i]);
if (a2 == b2) {
if (a2 % 2 == 0) ans += a[i]; else ans += b[i];
}
else if (b2 - a2 >= 2) ans += a[i];
else ans += b[i];
}
}
cout << ans;
}
main() {
ios_base::sync_with_stdio(0);
cin.tie(0);
if (fopen(task".inp", "r")) {
fin(task); fou(task);
}
int t = 1; //cin >> t;
while(t--) solve();
cerr << "\n" << 1.0 * clock() / CLOCKS_PER_SEC << "s ";
}
