codeforces/cpp/158A.cpp

#include <iostream>

using namespace std;

int main()
{
    int k, n, count = 0;
    cin >> k >> n;
    int arr[k];
    for (int i = 0; i < k; i++)
    {
        cin >> arr[i];
    }
    for (int i = 0; i < k; i++)
    {
        if (arr[i] > 0 && arr[i] >= arr[n - 1])
        {
            count++;
        }
    }
    cout << count << endl;
    return 0;
}