import java.math.BigDecimal;
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner in = new Scanner(System.in);
        BigDecimal X = in.nextBigDecimal();
        BigDecimal yen = new BigDecimal("100");
        BigDecimal rate = new BigDecimal("1.01");
        int count = 0;
        while (yen.compareTo(X)<0){
            yen = new BigDecimal(yen.multiply(rate).toString().split("\\.")[0]);
            count++;
        }
        System.out.print(count);
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz