#include <bits/stdc++.h>
#define F first
#define S second
using namespace std;
const int maxn = 2 * 1e5 + 7;
const int LOG = 31;
const long long MOD = (long long)(1e9) + 7;
const long long base = 311;
const int ALP_BET = 26;
typedef pair<int, int> ii;
typedef pair<int, long long> il;
typedef pair<long long, int> li;
typedef pair<long long, long long> ll;
int n, k;
ii a[maxn];
int t[maxn];
namespace SUB1 {
long long ans = 0;
void solve(){
ans = 0;
for(int i = 1; i <= n; ++i){
for(int j = 1; j <= k; ++j) if(a[i].F <= t[j]){
swap(a[i].F, a[i].S);
}
ans = ans + 1LL * a[i].F;
}
cout << ans << "\n";
return;
}
};
namespace FULL{
struct Fenwick_Tree{
int size;
vector<int> sums;
void init(int n){
size = n;
sums.assign(n + 7, 0);
return;
}
void update(int id, int val){
for(int i = id; i <= size; i = i | (i + 1)){
sums[i] = sums[i] + val;
}
return;
}
int get_pre(int id){
int res = 0;
for(int i = id; i >= 1; i = (i & (i + 1)) - 1){
res = res + sums[i];
}
return res;
}
int get_suffix(int id){
int res = get_pre(k) - get_pre(id - 1);
return res;
}
};
struct SegTree{
int size;
vector<int> maxs;
void init(int n){
size = n;
maxs.assign(n * 4 + 7, 0);
return;
}
void update(int id, int l, int r, int u, int val){
if(u < l || u > r)
return;
if(l == r){
maxs[id] = max(maxs[id], val);
return;
}
int mid = (l + r) / 2;
update(id * 2, l, mid, u, val);
update(id * 2 + 1, mid + 1, r, u, val);
maxs[id] = max(maxs[id * 2], maxs[id * 2 + 1]);
return;
}
void update(int id, int pos){
update(1, 1, size, id, pos);
return;
}
int get_max(int id, int l, int r, int u, int v){
if(v < l || u > r)
return 0;
if(u <= l && r <= v){
return maxs[id];
}
int mid = (l + r) / 2;
return max(get_max(id * 2, l, mid, u, v), get_max(id * 2 + 1, mid + 1, r, u, v));
}
int get_max(int l, int r){
return get_max(1, 1, size, l, r);
}
};
bool cmp(ii a, ii b){
return max(a.F, a.S) < max(b.F, b.S);
}
long long ans;
ii arr[maxn];
SegTree st;
Fenwick_Tree BIT;
void solve(){
// INIT
ans = 0;
for(int i = 1; i <= k; ++i)
arr[i] = {t[i], i};
sort(arr + 1, arr + k + 1);
sort(a + 1, a + n + 1, cmp);
BIT.init(k);
for(int i = 1; i <= k; ++i)
BIT.update(i, 1);
st.init(k);
int id = 0;
for(int i = 1; i <= n; ++i){
if(a[i].F == a[i].S){
ans = ans + 1LL * a[i].F;
continue;
}
int val = max(a[i].F, a[i].S);
while(id < k && val > arr[id + 1].F){
++id;
int pos = arr[id].S;
BIT.update(pos, -1);
st.update(id, pos);
}
// CAL_ANS
int LOW = min(a[i].F, a[i].S);
int l = 1, r = id, res = -1;
while(l <= r){
int mid = (l + r) / 2;
if(arr[mid].F >= LOW){
res = mid;
r = mid - 1;
} else
l = mid + 1;
}
if(res == -1){
int num = BIT.get_pre(k);
if(num % 2 == 0)
ans = ans + 1LL * a[i].F;
else
ans = ans + 1LL * a[i].S;
} else{
int pos = st.get_max(res, id);
int num = BIT.get_suffix(pos + 1);
if(a[i].F < a[i].S)
swap(a[i].F, a[i].S);
if(num % 2 == 0)
ans = ans + 1LL * a[i].F;
else
ans = ans + 1LL * a[i].S;
}
}
cout << ans << "\n";
return;
}
}
int main()
{
ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
cin >> n >> k;
for(int i = 1; i <= n; ++i)
cin >> a[i].F >> a[i].S;
for(int i = 1; i <= k; ++i)
cin >> t[i];
// SUB1::solve();
FULL::solve();
return 0;
}
