function Main(input) {
  input = input.split("\n");

  X = parseInt(input[0]);

  let current = 100;
  let year = 0;

  while (current < X) {
    year++;

    current = parseInt(current * 1.01);
  }

  console.log(year);
}

Main(require("fs").readFileSync("/dev/stdin", "utf8"));
