Wordcount with histogram written in C

wordcount-histogram.c

#include <stdio.h>
#include <stdlib.h>

#define MAXWORDLEN 20 // Maximum length of a word
#define IN 1          // Inside a word
#define OUT 0         // Outside a word

int main(void)
{
    int c;
    int words[MAXWORDLEN] = {0};
    int longest_word = 0;
    int wordcount = 0;
    int state = OUT;

    while ((c = getchar()) != EOF)
    {
        if (c == ' ' || c == '\n' || c == '\t')
        {
            if (state == IN && wordcount <= MAXWORDLEN)
            {
                words[wordcount]++;
                longest_word = (words[wordcount] > longest_word) ? words[wordcount] : longest_word;
            }
            state = OUT;
        }
        else
        {
            if (state == OUT)
            {
                wordcount = 0;
                state = IN;
            }
            ++wordcount;
        }
    }

    for (int i = longest_word; i >= 1; i--)
    {
        for (int j = 0; j < MAXWORDLEN; j++)
        {
            if (words[j] >= i)
            {
                printf("  *");
            }
            else
            {
                printf("   ");
            }
        }
        printf("\n");
    }

    for (int i = 0; i < MAXWORDLEN; i++)
        printf("---");

    printf("\n");

    for (int i = 0; i < MAXWORDLEN; i++)
        printf("%3d", i);

    return 0;
}