[Python3] priority queue
Please pull this commit for solutions of weekly 281. \n\n\nclass Solution:\n    def repeatLimitedString(self, s: str, repeatLimit: int) -> str:\n        pq = [(
Please pull this [commit](https://github.com/gaosanyong/leetcode/commit/793daa0aab0733bfadd4041fdaa6f8bdd38fe229) for solutions of weekly 281. \n\n```\nclass Solution:\n    def repeatLimitedString(self, s: str, repeatLimit: int) -> str:\n        pq = [(-ord(k), v) for k, v in Counter(s).items()] \n        heapify(pq)\n        ans = []\n        while pq: \n            k, v = heappop(pq)\n            if ans and ans[-1] == k: \n                if not pq: break \n                kk, vv = heappop(pq)\n                ans.append(kk)\n                if vv-1: heappush(pq, (kk, vv-1))\n                heappush(pq, (k, v))\n            else: \n                m = min(v, repeatLimit)\n                ans.extend([k]*m)\n                if v-m: heappush(pq, (k, v-m))\n        return "".join(chr(-x) for x in ans)\n```
['Python3']