#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; for(int i = 0; i < n; i++){ int u, v; cin >> u >> v; T.push_back({v, u}); } sort(T.rbegin(), T.rend()); vector<int> Q; for(int i = 0; i < m; i++){ int q; cin >> q; Q.push_back(q); } 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; }