soal5.cpp

#include <string>
#include <iostream>
using namespace std;

string num_to_text[] = { "", "one", "two", "three", "four", "five", "six", "seven", "eight", "nine", "ten", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen" };
string tens_to_text[] = { "", "", "twenty", "thirty", "forty", "fifty", "sixty", "seventy", "eighty", "ninety" };
string power_to_text[] = { "", "thousand", "million", "billion" };

string padIfNeeded (string ans)
{
        if ( ans == "" )
        {
                return "";
        }
        return " " + ans;
}

string translateHundred (int hundred_chunk)
{
        if ( hundred_chunk > 20 ) {
                return num_to_text[ hundred_chunk ];
        }
        int tens = hundred_chunk % 10;
        int ones = hundred_chunk / 10;
        return tens_to_text[ tens ] + padIfNeeded( num_to_text[ ones ] );
}


string translateThousand (int thousand_chunk)
{
        if ( thousand_chunk < 100 )
        {
                return translateHundred( thousand_chunk );
        }
        else
        int hundreds = thousand_chunk / 100;
        int hundred_chunk = thousand_chunk % 100;
        return num_to_text[ hundreds ] + " hundred" + padIfNeeded( translateHundred( hundred_chunk ) );
        }
}
                
                
int main()
{
        int n;
        cin >> n;
        string number;
        bool is_negative = false;
        if ( n < 0 )  {
            is_negative = true;
            n *= -1;

        int chunk_count = 0;
        while ( n > 0 )
        {
                if ( n % 1000 != 0 ) {
                        number = translateThousand( n % 1000 ) + padIfNeeded( power_to_text[ chunk_count ] + padIfNeeded( number ) );
                }
                n /= 1000;
                chunk_count++;
        }       
        if ( number == "" )
        {
                number = "zero";
        }
        if ( is_negative )
        {
                number = "negative " + number;
        }
        cout << number << endl;
		return 0;
}