从文件流中读取第K大的数

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int getKthLargest(std::istream &numStream, uint32_t k) { if (!numStream.good()) { throw std::invalid_argument("numStream"); } if (k == 0) { throw std::invalid_argument("k"); } try { auto initHeap = std::vector<int>(k, INT_MIN); std::priority_queue<int, vector<int>, std::greater<int>> minHeap(initHeap.begin(), initHeap.end()); int num; while (!numStream.eof()) { numStream >> num; if (numStream.fail()) { // bad format number continue; } minHeap.push(num); minHeap.pop(); } // assume input stream doesn't have any number == INT_MIN // to solve this problem, more solid why is adding a counter for input stream // but it will raise up another issue, stream length might be overflow. // to solve this problem, could stop counting when count == k. int result = minHeap.top(); if (result == INT_MIN) { // log } return result; } catch (exception ex) { throw; } }