水

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace _158A
{
    class Program
    {
        static void Main(string[] args)
        {
            int[] arr = Console.ReadLine().Split().Select(i => int.Parse(i)).ToArray();
            int n = arr[0];
            int k = arr[1] - 1;
            int[] score = Console.ReadLine().Split().Select(i => int.Parse(i)).ToArray();
            if (score[k] > 0)
            {
                int s = score[k];
                while(k < n && score[k] == s)
                {
                    k++;
                }
            }
            else
            {
                while(k >= 0 && score[k] <= 0)
                {
                    k--;
                }
                k++;
            }
            Console.WriteLine(k);
        }
    }
}