#include<bits/stdc++.h> #define ff first #define ss second #define pb push_back #define mp make_pair #define int long long using namespace std; const int md = 1e9 + 7; const int maxn = 5e5; signed main(){ int n, m; cin >> n >> m; vector<array<int, 2>> T(n); for(int i = 0; i < n; i++){ cin >> T[i][1] >> T[i][0]; } sort(T.rbegin(), T.rend()); vector<int> Q(m); for(int i = 0; i < m; i++){ cin >> Q[i]; } sort(Q.rbegin(), Q.rend()); int j = 0; vector<int> g; int cur = 0; for(int i = 0; i < n; i++){ if(T[i][1] <= Q[j]){ j += 1; } } cout << j; }