1700.cpp

#include <bits/stdc++.h>
#define fastio ios_base::sync_with_stdio(0), cin.tie(0), cout.tie(0)

#define ll long long
using namespace std;

const ll INF = 1e9 + 7;
const ll DIV = 987654321;

int n, k;
int arr[101];

int inq[101];
set<pair<int,int>> st;
int main()
{
    fastio;
    cin >> n >> k;
    for(int i =0 ;i < k;i++){
        cin >> arr[i];
    }

    int ans = 0;
    memset(inq, -1, sizeof inq);

    for(int i =0 ;i < k;i++){
        int j = i + 1;
        for(;j < k && arr[j] != arr[i];j++);
        if(inq[arr[i]] != -1){
            st.erase({inq[arr[i]], arr[i]});
            st.insert({j, arr[i]});
            inq[arr[i]] = j;
            continue;
        }
        if(st.size() == n){
            ans++;
            auto[a, b] = *(--st.end());
            inq[b] = -1;
            st.erase(--st.end());
        }
        inq[arr[i]]=j;
        st.insert({j, arr[i]});
    }
    cout << ans;
    return 0;
}