[Project Euler / 17]

Problem 17
17 May 2002

If the numbers 1 to 5 are written out in words: one, two, three, four, five, then there are 3 + 3 + 5 + 4 + 4 = 19 letters used in total.

If all the numbers from 1 to 1000 (one thousand) inclusive were written out in words, how many letters would be used?

NOTE: Do not count spaces or hyphens. For example, 342 (three hundred and forty-two) contains 23 letters and 115 (one hundred and fifteen) contains 20 letters. The use of "and" when writing out numbers is in compliance with British usage.

package com.tistory.honeybox.Euler;

import java.io.File;
import java.io.FileNotFoundException;
import java.io.PrintWriter;
public class Euler17 
{
	static String getTenUnit(int num)
	{
		switch(num)
		{
		case 0:
			return "ten";
		case 1:
			return "eleven";
		case 2:
			return "twelve";
		case 3:
			return "thirteen";
		case 4:
			return "fourteen";
		case 5:
			return "fifteen";
		case 6:
			return "sixteen";
		case 7:
			return "seventeen";
		case 8:
			return "eighteen";
		case 9:
			return "nineteen";
		}
		return null;
	}
	static String getNum(int num)
	{
		switch(num)
		{
		case 0:
			return "";
		case 1:
			return "one";
		case 2:
			return "two";
		case 3:
			return "three";
		case 4:
			return "four";
		case 5:
			return "five";
		case 6:
			return "six";
		case 7:
			return "seven";
		case 8:
			return "eight";
		case 9:
			return "nine";
		}
		return null;
	}
	static String getJarisu(int size,int num)
	{
		switch(size)
		{
		case 4: //천자리
			return getNum(num)+"thousand";
		case 3: //백자리
		case 0:
			switch(num)
			{
			case 0:return "";
			default:return getNum(num)+"hundred";
			}
		case 2: //십자리
			switch(num)
			{
			case 0:
				return "";
			case 1:
				return "";
			case 2:
				return "twenty";
			case 3:
				return "thirty";
			case 4:
				return "forty";
			case 5:
				return "fifty";
			case 6:
				return "sixty";
			case 7:
				return "seventy";
			case 8:
				return "eighty";
			case 9:
				return "ninety";
			}
		case 1:
			return getNum(num);
		default:
			return null;
		}


	}

	static String readInEnglish(String strNum)
	{
		String ret="";

		for(int i = 0 ; i < strNum.length() ; i++)
		{
			if(strNum.length()-i==2 
					&& (Integer.parseInt(strNum.charAt(i)+"")==1))
			{
				ret+=getTenUnit(Integer.parseInt(strNum.charAt(i+1)+""));
				return ret;
			}


			ret +=getJarisu(strNum.length()-i
					,Integer.parseInt(strNum.charAt(i)+""));
			if(strNum.length()-i==3)
			{
				if(strNum.charAt(strNum.length()-(i+1))!= '0'
					|| strNum.charAt(strNum.length()-(i+2))!= '0')
				{
					ret+="and";
				}
			}
		}

		return ret;
	}
	public static void main(String [] args) throws FileNotFoundException
	{


		
		PrintWriter out = new PrintWriter(new File("out"));
		int total=0;
		StringBuffer strBuffer = new StringBuffer();
		for(int i = 1 ; i <= 1000 ;i++)
		{
			String temp = readInEnglish(i+"");
			strBuffer.append(temp);
			total += temp.trim().length();
			System.out.print(temp);
			out.println(temp);
		}
		System.out.println(strBuffer);
		System.out.print("정답: " +total);
	}



}