HDU 1727 Hastiness

#include<stdio.h>
#include<math.h>
#include<string.h>
#include<stdlib.h>
#include<ctype.h>
#define max(a, b)(a < b ? a : b)
#define N 10010

char s[10][10] = {"one", "two", "three", "four", "five", "six", "seven","eight", "nine", "ten"};
char s1[10][10] = {"ten", "twenty", "thirty", "forty", "fifty", "sixty", "seventy", "eighty", "ninety"};
char s2[10][10] = {"eleven", "twelve", "thirteen", "fourteen", "fifteen", "sixteen", "seventeen", "eighteen", "nineteen"};

int main()
{
    int n;
    int a[N], j, i, f, g;
    while(scanf("%d", &n) != EOF)
    {
        j = 0, f = 0, g = 0;
        memset(a, 0, sizeof(a));
        if(n == 0)
            printf("zero");
        else
        {
            while(n)
            {
                a[j++] = n % 10;
                n /= 10;
            }
        }
        if(j == 1)
            printf("%s", s[a[0] - 1]);
        else
        {
            for(i = j - 1 ; i >= 0 ; i--)
            {
                if(i == 3)
                    printf("%s thousand", s[a[i] - 1]), f = 1;
                else if(i == 2)
                {
                    if(a[i] != 0)
                    {
                        if(f == 1)
                            printf(" and ");
                        printf("%s hundred", s[a[i] - 1]);
                    }
                    if(a[i - 1] != 0 || a[i - 2] != 0)
                        g = 1;

                }
                else if(i == 1)
                {
                    if(g == 1)
                        printf(" and ");
                    if(a[i] == 1 && a[i - 1] != 0)
                        printf("%s", s2[a[i - 1] - 1]);
                    else
                    {
                        if(a[i] == 0)
                            printf("%s", s[a[i - 1] - 1]);
                        else
                        {
                            if(a[i - 1] == 0)
                                printf("%s", s1[a[i] - 1]);
                            else
                            {
                                printf("%s-%s", s1[a[i] - 1], s[a[i - 1] - 1]);
                            }
                        }
                    }
                }
            }
        }
        printf("
");
    }
    return 0;
}

Problem Description

How many problems did you AC?
When you read this problem, don’t hasty and careless, this is also simple, haha, I didn’t cheat you.
The game over soon, WisKey starts using English begin countdown. He not only have no gene in math, but also bad in English. Fortunately, He met you who have gift in programming. So please help him to translate. 

Input

Give you an integer T, output T in English, and note that all of words are lower case. (0<=T<=9999)

Output

One answer One line.
Details see sample.

Sample Input

2034
1234
123
24
0

Sample Output

two thousand and thirty-four
one thousand and two hundred and thirty-four
one hundred and twenty-three
twenty-four
zero

Author

威士忌

Source

HZIEE 2007 Programming Contest