Description
How far can you make a stack of cards overhang a table? If you have one card, you can create a maximum overhang of half a card length. (We‘re assuming that the cards must be perpendicular to the table.) With two cards you can make the top card overhang the bottom one by half a card length, and the bottom one overhang the table by a third of a card length, for a total maximum overhang of 1/2 + 1/3 = 5/6 card lengths. In general you can make n cards overhang by 1/2 + 1/3 + 1/4 + ... + 1/(n + 1) card lengths, where the top card overhangs the second by 1/2, the second overhangs tha third by 1/3, the third overhangs the fourth by 1/4, etc., and the bottom card overhangs the table by 1/(n + 1). This is illustrated in the figure below.

import java.util.*;   public class Main {       public static void main(String[] args) {           Scanner cin = new Scanner(System.in);           String str;           int maxCardNum = 0;           while(cin.hasNext())           {               str = cin.nextLine();               if(str.equals("0.00"))                   break;               float len = Float.valueOf(str).floatValue();               maxCardNum = getCardNum(len);               System.out.println(maxCardNum + " card(s)");           }         }              private static int getCardNum(float len)       {           float value = http://www.mamicode.com/0;           int index = 2;             while (value < len)           {               value += 1.0/index;               index++;           }                          return index-2;       }     }