Java实现 洛谷 P1423 小玉在游泳

import java.util.Scanner;


public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		
		double x = in.nextDouble();
		
		double sum = 0;
		int i = 1;
		while( !(x<sum) ){
			sum = sum + 2*Math.pow(0.98, i-1);
			i++;
		}
		
		System.out.println(i-1);
	}

}