May anyone find some bugs from this code?

[Mathsniper]

I have spent lots of time to debug but no result get. Problem from http://acm.hnu.cn:8080/online/?actio...=show&id=10190
My idea:
1) Calcuating the letter how often they appear.
2) Find the topest apearing letter.
3) If the current line number is less then current alphabet letter appearing number. Then print a asterisk, otherwise print a space. The space after the last asterisk should not be printed.
Here is my code

#include <stdio.h>
#include <ctype.h>
#include <string.h>
#define MAX_S 80

int alphabet[26];
int height;

void vertHistogram()
{
    int i, j, k;
    for (i = height; i >= 1; i--) {
        k = 0;
        for (j = 0; j < 26; j++)
            if (alphabet[j] >= i) k = j;
        for (j = 0; j <= k; j++) {
            if (alphabet[j] >= i)
                printf("*");
            else printf(" ");
            if (j < k) printf(" ");
        }
        printf("\n");
    }
    for (i = 0; i < 26; i++) {
        printf("%c", 'A'+i);
        if (i < 25) printf(" ");
    }
    printf("\n");
}

int main()
{
    char s[MAX_S];
    int i, j;
    for (i = 0; i < 26; i++)
        alphabet[i] = 0;
    for (i = 1; i <= 4; i++) {
        fgets(s, sizeof s, stdin);
        for (j = 0; j < strlen(s)-1; j++) {
            if (isalpha(s[j]) && isupper(s[j]))
                alphabet[(int)(s[j]-'A')]++;
        }
    }
    height = 0;
    for (i = 0; i < 26; i++)
        if (height < alphabet[i])
            height = alphabet[i];
    vertHistogram();
    return 0;
}

[Salem]

So what's the question?
I'm guessing it's the "no spaces after last *" - am I right?

What have you managed to figure out so far?

You can't just dump your question and current code, and expect someone else to figure out what it ought to do / should do.

[Mathsniper]

sorry for my lazy habit and the wrong link. The problem is calcuating how often does the letter appear from A to Z. I don't know why I get the wrong answer. For example, I input the following data

AAABBEECDF23455K
HAHKERH355;22AVcadf34gg
ER{GHKLVN:>ZEasdfhF
uepwrhdfnwe490

The output from my prog

*       *
*       *     *
*       *     *     *
* *     * *   *     *             *       *
* * * * * * * *     * *   *       *       *       *
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

What's the problem here?

[Dave_Sinkula]

What's the problem here?

Do you mean you wish to count lowercase letters in the totals?

            if (isalpha(s[j]))
                alphabet[toupper(s[j])-'A']++;