程式語言 - LeetCode - C - 3606. Coupon Code Validator

題目：


解答：

bool is_valid_code(const char *p)
{
    int i = 0;
    int len = strlen(p);

    for (i = 0; i < len; i++) {
        if ((p[i] >= 'a' && p[i] <= 'z') ||
            (p[i] >= 'A' && p[i] <= 'Z') ||
            (p[i] >= '0' && p[i] <= '9') ||
            (p[i] == '_'))
        {
            continue;
        }

        return false;
    }

    return true;
}

int business_index(const char *p)
{
    int i = 0;
    const char *cat[] = { "electronics", "grocery", "pharmacy", "restaurant", NULL };

    for (i = 0; cat[i]; i++) {
        if (!strcmp(p, cat[i])) {
            return i;
        }
    }

    return -1;
}

int mysort(const void *a, const void *b)
{
    return strcmp(*(const char **)a, *(const char **)b);
}

/**
 * Note: The returned array must be malloced, assume caller calls free().
 */
char** validateCoupons(char** code, int codeSize, char** businessLine, int businessLineSize, bool* isActive, int isActiveSize, int* returnSize)
{
    int i = 0;
    int j = 0;
    int cnt[4] = { 0 };
    char **t[4] = { 0 };
    char **r = calloc(codeSize, sizeof(char *));

    for (i = 0; i < 4; i++) {
        t[i] = calloc(codeSize + 1, sizeof(char *));
    }

    for (i = 0; i < codeSize; i++) {
        int idx = 0;

        if (code[i][0] == 0) {
            continue;
        }

        if (isActive[i] == false) {
            continue;
        }

        if (is_valid_code(code[i]) == false) {
            continue;
        }

        idx = business_index(businessLine[i]);
        if (idx < 0) {
            continue;
        }

        t[idx][cnt[idx]] = calloc(sizeof(char), strlen(code[i]) + 1);
        strcpy(t[idx][cnt[idx]], code[i]);
        cnt[idx] += 1;
    }

    *returnSize = 0;
    for (i = 0; i < 4; i++) {
        if (cnt[i] == 0) {
            continue;
        }

        qsort(t[i], cnt[i], sizeof(char *), mysort);
        for (j = 0; t[i][j]; j++) {
            r[(*returnSize)++] = t[i][j];
        }
    }

    return r;
}