import java.util.Scanner;

public class Main {
	public static void main(String[] args){
		try(Scanner sc = new Scanner(System.in)) {
			

			long x = sc.nextLong();
			
//			List<Double> compoundIntereset = new ArrayList<>();
			
			long p = 100;
			long i = 0;
			
			while(p < x) {
				
				p = (long)((double)p * 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