import java.util.*;

public class Main {
	public static void main(String[] args) {
	    Scanner sc = new Scanner(System.in);
        long target = Long.valueOf(sc.next());
        long yen = 100;
        int count = 0;

        for(;;) {
            yen *= 1.01;
            count++;
            if(yen >= target) break;
        }
        System.out.println(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