#include<bits/stdc++.h> #define ff first #define ss second #define pb push_back #define mp make_pair using namespace std; const int md = 1e9 + 7; const int maxn = 5e5; struct Mint { int v; static const int md = 1e9 + 7; Mint(long long _v = 0) { v = int((_v % md + md) % md); } Mint& operator+=(const Mint& other) { v += other.v; if (v >= md) v -= md; return *this; } Mint& operator-=(const Mint& other) { v -= other.v; if (v < 0) v += md; return *this; } Mint& operator*=(const Mint& other) { v = int((1LL * v * other.v) % md); return *this; } friend Mint operator+(Mint a, const Mint& b) { return a += b; } friend Mint operator-(Mint a, const Mint& b) { return a -= b; } friend Mint operator*(Mint a, const Mint& b) { return a *= b; } friend Mint power(Mint a, long long b) { Mint res = 1; while (b > 0) { if (b & 1) res *= a; a *= a; b >>= 1; } return res; } friend ostream& operator<<(ostream& os, const Mint& m) { return os << m.v; } friend istream& operator>>(istream& is, Mint& m) { long long x; is >> x; m = Mint(x); return is; } explicit operator bool() const { return v != 0; } bool operator==(int x) const { return v == ((x % md + md) % md); } bool operator!=(int x) const { return v != ((x % md + md) % md); } }; 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; }