import std.stdio, std.string, std.conv;
import std.typecons;
import std.algorithm, std.array, std.range, std.container;
import std.math;

void main() {
	auto X = readln.split[0].to!long;
	long money = 100;
	foreach (i; 1 .. 4000) {
	    money = cast(long) floor(money * 1.01);
	    if (money >= X) { writeln(i); break; }
	}
}

