function Main(INPUT){
  const input=INPUT.split("\n");
  const N=parseInt(input[0]);
  let r=9%N;
  let K=1;
  while(r!=0){
    K++;
    r=(r*10+9)%N;
  }
  console.log(K);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));