2781. 最长合法子字符串的长度

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C代码：滑动窗口、哈希表

typedef struct{char* str;UT_hash_handle hh;
} HashTable;HashTable* head;void AddToHash(char* str) {HashTable* out = (HashTable*)malloc(sizeof(HashTable));out->str = str;HASH_ADD_STR(head, str, out);
}bool FindStr(char* word, int r, int j) {HashTable* out = NULL;char* str = (char*)malloc(sizeof(char) * 11);str[0] = '\0';strncat(str, word + j, r - j + 1);HASH_FIND_STR(head, str, out);return out != NULL;
}int longestValidSubstring(char * word, char ** forbidden, int forbiddenSize){head = NULL;for (int i = 0; i < forbiddenSize; ++i) {AddToHash(forbidden[i]);}int len = strlen(word);int l = 0;int ans = 0;for (int r = 0; r < len; ++r) {for (int j = r; j >= fmax(l, r - 10 + 1); --j) {if (FindStr(word, r, j)) {l = j + 1;break;}}if (r >= l) {ans = fmax(ans, r - l + 1);}}return ans;
}