#include <stdio.h>

int main() {
  unsigned long level_deposit, deposit = 100;
  short output_year = 0;
  float interest_rate = 0.01;

  scanf("%ld", &level_deposit);

  while(deposit < level_deposit) {
    deposit = deposit + deposit * interest_rate;
    output_year += 1;
  }

  printf("%hd", output_year);
  printf("%c", '\n');

  return 0;
}
