#include <cmath>
#include <cstdio>
#include <vector>
#include <iostream>
#include <algorithm>
using namespace std;


int main() {
    /* Enter your code here. Read input from STDIN. Print output to STDOUT */   
    int n, k;
    cin>>n>>k;
    
    vector<int> arr(n);
    for(int i=0; i<n; i++){
        cin>>arr[i];
    }
    
    int mid = (0 + n)/2;
    cout<<mid;
    
    return 0;
}