How many anagrams

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

#define MAX_WORD_SIZE (50)

typedef struct {
    char* w1;
    char* w2;
} anagram_t;

int anagram(char* word1, char* word2)
{
    size_t i;
    char* w;

    if (strlen(word1) != strlen(word2))
        return 0;

    if (strcmp(word1, word2) == 0)
        return 0;

    for (i = 0; i < strlen(word1); ++i) {
        w = strchr(word2, word1[i]);
        if (w == NULL)
            return 0;
        *w = '-';
    }

    return 1;
}

int cmp(anagram_t* a, char* w1, char* w2)
{
    if (strcmp(a->w1, w1) == 0 &&
        strcmp(a->w2, w2) == 0)
        return 1;

    if (strcmp(a->w1, w2) == 0 &&
        strcmp(a->w2, w1) == 0)
        return 1;

    return 0;
}

int main(int argc, char** argv)
{
    char** words;
    char buff[MAX_WORD_SIZE];
    size_t p, w, mw, count, ma;
    int t;
    anagram_t** a;
    int c;
    FILE* fp;

    if (argc != 2)
        return 1;

    fp = fopen(argv[1], "r");
    if (fp == NULL) {
        printf("File not found.\n");
        return 1;
    }

    words = malloc(100 * sizeof(char*));
    if (words == NULL)
        return 1;

    w = 0;
    mw = 100;
    p = 0;
    while ((c = fgetc(fp)) != EOF) {
        if (c >= 'A' && c <= 'Z')
            c += 32;
        if (c < 'a' || c > 'z') {
            if (p <= 1) {
                p = 0;
                continue;
            }
            if (w == mw) {
                mw += 100;
                words = realloc(words, mw * sizeof(char*));
                if (words == NULL)
                    return 1;
            }
            words[w] = malloc(p + 1);
            if (words[w] == NULL)
                return 1;
            memcpy(words[w], buff, p);
            words[w][p] = '\0';
            w += 1;
            p = 0;
        } else {
            buff[p++] = c;
        }
    }

    fclose(fp);
    count = 0;
    ma = 50;
    a = malloc(ma * sizeof(anagram_t*));
    if (a == NULL)
        return 1;
    for (p = 0; p < w - 1; ++p) {
        for (mw = p + 1; mw < w; ++mw) {
            memcpy(buff, words[mw], strlen(words[mw]) + 1);
            if (anagram(words[p], buff)) {
                for (t = 0; t < count; ++t) {
                    if (cmp(a[t], words[p], words[mw])) {
                        t = -1;
                        break;
                    }
                }
                if (t > -1) {
                    if (count == ma) {
                        ma += 50;
                        a = realloc(a, ma *
                            sizeof(anagram_t*));
                        if (a == NULL)
                            return 1;
                    }
                    a[count] = malloc(sizeof(anagram_t));
                    a[count]->w1 = words[p];
                    a[count]->w2 = words[mw];
                    count += 1;
                }
            }
        }
    }

    printf("Number of anagrams: %lu\n", count);

    for (ma = 0; ma < count; ++ma)
        printf("%s, %s\n", a[ma]->w1, a[ma]->w2);
        free(a[ma]);
    free(a);

    for (ma = 0; ma < w; ++ma)
        free(words[ma]);
    free(words);
    return 0;
}