158A

process.stdin.resume();
    process.stdin.setEncoding("utf-8");

    let inputString = "";
    let currentLine = 0;

    process.stdin.on("data", (inputStdin) => {
        inputString += inputStdin;
    });

    process.stdin.on("end", (_) => {
        inputString = inputString
            .trim()
            .split("\n")
            .map((string) => {
                return string.trim();
            });

        main();
    });

    function readline() {
        return inputString[currentLine++];
    }

function main(){
  const topLine = readline();
  const racerAmount = parseInt(topLine.split(" ")[0]);
  const kthPlace = parseInt(topLine.split(" ")[1]) - 1;

  const arr = readline().split(" ").map(
    (el) => parseInt(el)
   );
  arr.sort(function(a,b){return b-a;});
  const goal = arr[kthPlace];

  let I = 0;
  let score = 0;
  while(I<arr.length){
    if( arr[I] >= goal && arr[I] > 0){
      score++;
    }
    I++;
  }

  console.log(score);
}