#include <bits/stdc++.h>
#define all(a) (a).begin(), (a).end()
using namespace std;
struct segtree {
vector<int> tree;
int offset = 1;
function<int(int, int)> f;
int I;
segtree(int n, function<int(int, int)> f, int I) : f(f), I(I) {
while (offset < n) offset *= 2;
tree.resize(offset << 1, I);
}
void update(int i, int x) {
i += offset;
tree[i] = f(tree[i], x);
while (i >>= 1) tree[i] = f(tree[i*2], tree[i*2 + 1]);
}
int query(int v, int l, int r, int ql, int qr) {
if (ql <= l && r <= qr) return tree[v];
if (qr < l || r < ql) return I;
int mid = l+r >> 1;
return f(
query(v*2, l, mid, ql, qr),
query(v*2+1, mid+1, r, ql, qr)
);
}
int query(int l, int r) {
return query(1, 0, offset - 1, l, r);
}
};
signed main() {
ios::sync_with_stdio(false);
cin.tie(nullptr); cout.tie(nullptr);
int n,k; cin >> n >> k;
int a[n], b[n], t[k];
for (int i = 0; i < n; cin >> a[i] >> b[i++]);
for (int& x : t) cin >> x;
vector<int> compress;
for (int i = 0; i < n; i++)
compress.push_back(a[i]), compress.push_back(b[i]);
for (int i = 0; i < k; i++)
compress.push_back(t[i]);
sort(all(compress));
auto comp = [&](int x) {
return lower_bound(all(compress), x) - compress.begin();
};
segtree s(2*n + k, [&](int x, int y) { return max(x, y); }, -1);
for (int i = 0; i < k; i++) {
s.update(comp(t[i]), i);
}
vector<int> points[k];
vector<int> final;
for (int i = 0; i < n; i++) {
if (a[i] == b[i]) {
final.push_back(i);
continue;
}
int last = s.query(
comp(min(a[i], b[i])),
comp(max(a[i], b[i])) - 1);
if (last == -1) final.push_back(i);
else points[last].push_back(i);
}
s = segtree(2*n + k, [&](int x, int y) { return x + y; }, 0);
string res(n, '0');
for (int i = k-1; i >= 0; i--) {
for (int j : points[i]) {
int cnt = s.query(comp(max(a[j], b[j])), 2*n + k - 1);
res[j] = cnt % 2 ? 'A' : 'B';
if (a[j] > b[j])
res[j] ^= 'A' ^ 'B';
}
s.update(comp(t[i]), 1);
}
for (int j : final) {
int cnt = s.query(comp(max(a[j], b[j])), 2*n + k - 1);
res[j] = cnt % 2 ? 'B' : 'A';
}
long long sum = 0;
for (int i = 0; i < n; i++) {
sum += res[i] == 'A' ? a[i] : b[i];
}
cout << sum;
return 0;
}
