#include <bits/stdc++.h>
using namespace std;
const int MAXN = 1e6 + 100;
struct A {
    int tag, idx, cnt;
    bool operator < (const A& x) const {
        if (cnt == x.cnt)
            return tag > x.tag;
        return cnt > x.cnt;
    }
};
int n, m, p[MAXN], c[MAXN], sz, ans;
priority_queue<A> que;
vector<int> v;
int main()
{
    ios::sync_with_stdio(false);
    cin.tie(0);cout.tie(0);
    cin >> n >> m;
    for (int i = 1; i <= m; i++) {
        cin >> p[i];
        v.push_back(p[i]);
    }
    sort(v.begin(), v.end());
    v.erase(unique(v.begin(), v.end()), v.end());
    for (int i = 1; i <= m; i++) {
        p[i] = lower_bound(v.begin(), v.end(), p[i]) - v.begin();
        if (c[p[i]] > 0) {
            c[p[i]]++;
            ans++;
        } else if (sz < n) {
            c[p[i]] = 1;
            que.push({i, p[i], 1});
            sz++;
        } else {
            while (que.top().cnt != c[que.top().idx]) {
                A tp = que.top();
                que.pop();
                que.push({tp.tag, tp.idx, c[tp.idx]});
            }
            c[que.top().idx] = 0;
            que.pop();
            c[p[i]] = 1;
            que.push({i, p[i], 1});
        }
    }
    cout << ans;
    return 0;
}