/*
Author: Nguyen Chi Thanh - High School for the Gifted - VNU.HCM (i2528)
*/
#include <bits/stdc++.h>
using namespace std;
/* START OF TEMPALTE */
// #define int long long
#define ll long long
#define ull unsigned long long
#define ld long double
#define pii pair<int, int>
#define pll pair<ll, ll>
#define fi first
#define se second
#define popcount __builtin_popcountll
#define all(x) (x).begin(), (x).end()
#define BIT(x, i) (((x) >> (i)) & 1)
#define MASK(x) (1ll << (x))
#define SZ(a) ((int32_t)a.size())
#define debug(a, l, r) {for (int _i = (l); _i <= (r); ++_i) cout << (a)[_i] << ' '; cout << '\n';}
template<class X, class Y>
bool minimize(X &x, const Y &y) {
if (x > y) {
x = y;
return true;
} else return false;
}
template<class X, class Y>
bool maximize(X &x, const Y &y) {
if (x < y) {
x = y;
return true;
} else return false;
}
/* END OF TEMPALTE */
const int MAXN = 2e5 + 5;
struct SegmentTreeMax {
int n;
vector<int> seg;
SegmentTreeMax() {}
SegmentTreeMax(int _n) : n(_n), seg(4 * n + 5, 0) {}
void init(int _n) {*this = SegmentTreeMax(_n);}
void update(int id, int l, int r, int pos, int val) {
if (pos < l || pos > r) return;
if (l == r) {
maximize(seg[id], val);
return;
}
int mid = (l + r) >> 1;
update(id << 1, l, mid, pos, val);
update(id << 1 | 1, mid + 1, r, pos, val);
seg[id] = max(seg[id << 1], seg[id << 1 | 1]);
}
int get(int id, int l, int r, int u, int v) {
if (v < l || r < u) return 0;
if (u <= l && r <= v) return seg[id];
int mid = (l + r) >> 1;
int getLeft = get(id << 1, l, mid, u, v);
int getRight = get(id << 1 | 1, mid + 1, r, u, v);
return max(getLeft, getRight);
}
void update(int pos, int val) {update(1, 1, n, pos, val);}
int get(int u, int v) {
if (u > v) return 0;
return get(1, 1, n, u, v);
}
};
struct FenwickTree {
int n;
vector<int> fen;
FenwickTree() {}
FenwickTree(int _n) : n(_n), fen(n + 5) {}
void init(int _n) {*this = FenwickTree(_n);}
void update(int idx, int v) {
assert(idx > 0);
for (int i = idx; i <= n; i += i & -i)
fen[i] += v;
}
int get(int idx) {
int sum = 0;
for (int i = idx; i; i -= i & -i)
sum += fen[i];
return sum;
}
int query(int l, int r) {
if (l > r) return 0;
return get(r) - get(l - 1);
}
};
struct Normalize {
vector<int> vals;
void add(int v) {vals.push_back(v);}
void build() {
sort(all(vals));
vals.erase(unique(all(vals)), end(vals));
}
int get(int v) {
return (int)(lower_bound(all(vals), v) - begin(vals)) + 1;
}
void compress(int &v) {v = get(v);}
int size() {return SZ(vals);}
int restore(int v) {
return vals[v - 1];
}
};
struct Card {
int upside, downside;
Card (int a = 0, int b = 0) : upside(a), downside(b) {}
void output() {cout << upside << ' ' << downside << '\n';}
};
// How many number >= x in range [l, r]
struct Query {
int l, r, x, id;
bool operator < (const Query &other) const {
return x > other.x;
}
void output() {
cout << "Query [" << l << ", " << r << "], x = " << x << ", id = " << id << "\n";
}
};
int n, q, operation[MAXN], lastPos[MAXN], numChanged[MAXN];
Card cards[MAXN];
Normalize comp;
SegmentTreeMax seg;
FenwickTree fen;
void init() {
cin >> n >> q;
for (int i = 1; i <= n; ++i) {
int a, b; cin >> a >> b;
cards[i] = {a, b};
comp.add(a); comp.add(b);
}
for (int i = 1; i <= q; ++i) {
int x; cin >> x;
operation[i] = x; comp.add(x);
}
comp.build();
for (int i = 1; i <= n; ++i) {
comp.compress(cards[i].upside);
comp.compress(cards[i].downside);
}
for (int i = 1; i <= q; ++i) comp.compress(operation[i]);
// for (int i = 1; i <= n; ++i) cards[i].output();
// debug(operation, 1, q);
}
void solve() {
seg.init(comp.size() + 5);
fen.init(q + 5);
for (int i = 1; i <= q; ++i)
seg.update(operation[i], i);
for (int i = 1; i <= n; ++i) {
int l = cards[i].upside, r = cards[i].downside;
if (l > r) swap(l, r);
lastPos[i] = seg.get(l, r - 1);
}
// debug(lastPos, 1, n);
vector<Query> queries;
for (int i = 1; i <= n; ++i) {
if (lastPos[i] >= q) continue;
int target = max(cards[i].upside, cards[i].downside);
queries.push_back({lastPos[i] + 1, q, target, i});
}
sort(all(queries));
vector<pii> vals;
for (int i = 1; i <= q; ++i)
vals.push_back({operation[i], i});
sort(all(vals), greater<pii>());
int ptr = 0;
for (auto &qry : queries) {
while (ptr < q && vals[ptr].fi >= qry.x) {
fen.update(vals[ptr].se, 1);
++ptr;
}
int cnt = fen.query(qry.l, qry.r);
numChanged[qry.id] = cnt;
}
// debug(numChanged, 1, n);
ll ans = 0;
for (int i = 1; i <= n; ++i) {
vector<int> face(2);
face[0] = cards[i].upside; face[1] = cards[i].downside;
if (lastPos[i] > 0 && face[0] < face[1])
swap(face[0], face[1]);
int original = comp.restore(face[numChanged[i] & 1]);
ans += (ll)original;
}
cout << ans;
}
signed main() {
#ifdef NCTHANH
freopen("input.txt", "r", stdin);
freopen("output.txt", "w", stdout);
#endif
ios_base::sync_with_stdio(0);
cin.tie(nullptr); cout.tie(nullptr);
init();
solve();
return 0;
}
