import java.util.Scanner;

public class Main {
    public static void main(final String args[]) {
        Scanner scan = new Scanner(System.in);
        double X = scan.nextDouble();
        double K = 100;
        int i = 0;
        while(X > K){
            K = Math.floor(K * 1.01);
            i++;
        }
        System.out.println(i);

    }
}

/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