#include <bits/stdc++.h>
using namespace std;
#pragma GCC optimize("Ofast,unroll-loops")
//pragma GCC target("avx2,popcnt,lzcnt,abm,bmi,bmi2,fma,tune=native")
#pragma GCC target("sse4")
using ll = long long;
using ld = long double;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pi3 = pair<pii, int>;
#define IOS ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
#define F first
#define S second
#define sz(x) x.size()
#define all(x) x.begin(), x.end()
#define pb push_back
#define cl clear
#define minr(a, b) a = min(a, b);
#define maxr(a, b) a = max(a, b);
#define shit cout << "shit\n" << flush;
#define tl while(1&1) continue;
#define FOR(i, st, nd) for(int i = st; i <= n; i++)
#define rand(l, r) uniform_int_distribution<int64_t>(l,r)(rng)
random_device device; default_random_engine rng(device());
const int Mod = 1e9 + 7; //998244353;
const int LG = 64;
const int SQ = 500;
const int Inf = 2e9 + 10;
const int maxN = 2e5 + 10;
const int maxC = 5e5 + 10;
int a[maxN];
int b[maxN];
vector <int> quest;
set <int> num;
unordered_map <int, int> NewVal;
struct SegTree {
struct Node {
int mx;
vector <int> query;
Node() {
mx = 0;
}
} t[maxC<<3];
void Add(int id, int L, int R, int idx, int val) {
if(idx < L or idx >= R)
return;
maxr(t[id].mx, val);
if(L+1 == R) {
t[id].query.pb(val);
return;
}
int mid = (L+R)>>1;
if(idx < mid)
Add(2*id+0, L, mid, idx, val);
else
Add(2*id+1, mid, R, idx, val);
}
void merge(int id, int L, int R) {
if(L+1 == R)
return;
int mid = (L+R)>>1;
merge(2*id+0, L, mid);
merge(2*id+1, mid, R);
int ptr1 = 0;
int ptr2 = 0;
while(ptr1 < sz(t[2*id+0].query) and ptr2 < sz(t[2*id+1].query)) {
if(t[2*id+0].query[ptr1] < t[2*id+1].query[ptr2]) {
t[id].query.pb(t[2*id+0].query[ptr1]);
ptr1++;
}
else {
t[id].query.pb(t[2*id+1].query[ptr2]);
ptr2++;
}
}
while(ptr1 < sz(t[2*id+0].query)) {
t[id].query.pb(t[2*id+0].query[ptr1]);
ptr1++;
}
while(ptr2 < sz(t[2*id+1].query)) {
t[id].query.pb(t[2*id+1].query[ptr2]);
ptr2++;
}
}
int GetMax(int id, int L, int R, int l, int r) {
if(l >= r)
return 0;
if(L == l and R == r)
return t[id].mx;
int ans = 0;
int mid = (L+R)>>1;
if(l < mid)
maxr(ans, GetMax(2*id+0, L, mid, l, min(mid, r)));
if(r > mid)
maxr(ans, GetMax(2*id+1, mid, R, max(l, mid), r));
return ans;
}
int GetCnt(int id, int L, int R, int l, int r, int v) {
if(L == l and R == r) {
auto it = lower_bound(all(t[id].query), v);
return int(t[id].query.end()-it);
}
int ans = 0;
int mid = (L+R)>>1;
if(l < mid)
ans += GetCnt(2*id+0, L, mid, l, min(mid, r), v);
if(r > mid)
ans += GetCnt(2*id+1, mid, R, max(l, mid), r, v);
return ans;
}
} s;
void Compress() {
int lst = 1;
for(auto it = num.begin(); it != num.end(); it++) {
NewVal[*it] = lst;
lst++;
}
}
int main() {
IOS;
int n, k;
cin >> n >> k;
for(int i = 1; i <= n; i++) {
cin >> a[i] >> b[i];
num.insert(a[i]);
num.insert(b[i]);
}
for(int i = 1; i <= k; i++) {
int x;
cin >> x;
quest.pb(x);
num.insert(x);
}
Compress();
int l = sz(num);
for(int i = 0; i < k; i++)
s.Add(1, 1, l+1, NewVal[quest[i]], i+1);
s.merge(1, 1, l+1);
ll ret = 0;
for(int i = 1; i <= n; i++) {
bool swaped = false;
int tmp = 0;
if(NewVal[a[i]] > NewVal[b[i]]) {
swap(a[i], b[i]);
swaped = true;
tmp = 1;
}
int LastFix = s.GetMax(1, 1, l+1, NewVal[a[i]], NewVal[b[i]]);
if(LastFix)
tmp = 1;
int ChangeCnt = s.GetCnt(1, 1, l+1, NewVal[b[i]], l+1, LastFix);
tmp = (tmp + (ChangeCnt % 2))%2;
if(tmp == 0)
ret += a[i];
else
ret += b[i];
}
cout << ret;
}
