#include <bits/stdc++.h>

using namespace std;

int main()
{
    iostream::sync_with_stdio(0);
    cin.tie(0);
    unsigned long long n,k;
    int pont =0;
    cin >> n;
    cin >> k;
    bool nem;
    vector<unsigned long long> alma;
    vector<unsigned long long>alma2=alma;
    unsigned long long current;
    for(int i =0; i<k;i++)
    {
        cin >> current; alma.push_back(current);
    }
    sort(alma2.begin(), alma2.end())
    alma2.push_back(n+1);
    int j =0;
    for(int i =0; i <k;i++)
    {
        igen = ture;
        while(alma2[j]<=alma[i])
        {
            if(igen)pont++;
            igen=false;
            j++;
        }
    }
    cout << pont;
}