387B - George and Round - CodeForces Solution

#include<bits/stdc++.h>
using namespace std;
#define AYAALI ios_base::sync_with_stdio(false);cin.tie(nullptr);cout.tie(nullptr);
#define FOR(i, a, b) for(int i = int(a); i < int(b); i++)
#define yes cout<<"YES\n";
#define no cout<<"NO\n";
#define ll long long
#define pb(x) push_back(x)
#define MP(x, y) make_pair(x,y)
#define fi first
#define se second
#define endl '\n'
#define all(v) v.begin(), v.end()
const double EPS = 1e-9;
const ll N=1e5+1;
//---------------------------------------------
void files(){
    freopen("highcard.in", "r", stdin);
    freopen("highcard.out", "w", stdout);
}

void solve(){
    ll n,m;
    cin>>n>>m;
    multiset<ll>v2;
    vector<ll>v1;
    for(int i=0;i<n;i++){
        ll x;cin>>x;
        v1.pb(x);
    }
    for(int i=0;i<m;i++){
        ll y;cin>>y;
        v2.insert(y);
    }
    ll cnt  = 0;
    for(int i=0;i<n;i++){
        if(v2.find(v1[i])!=v2.end() ){
           v2.erase(v2.find(v1[i]));
        }else if(v2.upper_bound(v1[i])!=v2.end()){
            v2.erase(v2.upper_bound(v1[i]));
        }else{
            cnt++;
        }
    }
    cout<<cnt;



}
int main() {
    ll t= 1;
    //cin>>t;
    //files();
    while(t--){
        solve();
    }


    return 0;
}