int main() { std::string inputLine; std::getline(std::cin, inputLine); size_t closingBracketIndex = inputLine.find(']'); if (closingBracketIndex == std::string::npos) { std::cerr << "Error: Invalid input format. Missing closing bracket for node values array." << std::endl; return 1; } std::string valuesString = inputLine.substr(0, closingBracketIndex + 1); valuesString.erase(std::remove(valuesString.begin(), valuesString.end(), '['), valuesString.end()); valuesString.erase(std::remove(valuesString.begin(), valuesString.end(), ']'), valuesString.end()); std::vector nodeValues; try { if (!valuesString.empty()) { std::stringstream ss(valuesString); std::string segment; while (std::getline(ss, segment, ',')) { if (!segment.empty()) { nodeValues.push_back(std::stoi(segment)); } } } } catch (const std::exception& e) { std::cerr << "Error parsing input values: " << e.what() << std::endl; return 1; } ListNode *head = nullptr; ListNode *current = nullptr; if (!nodeValues.empty()) { head = new ListNode(nodeValues[0]); current = head; for (size_t i = 1; i < nodeValues.size(); ++i) { current->next = new ListNode(nodeValues[i]); current = current->next; } } Solution sol; ListNode* newHead = sol.reverseList(head); std::cout << "["; current = newHead; while (current != nullptr) { std::cout << current->val; if (current->next != nullptr) { std::cout << ","; } current = current->next; } std::cout << "]" << std::endl; current = newHead; while (current != nullptr) { ListNode *temp = current; current = current->next; delete temp; } return 0; }

Reverse Linked List

Examples

Hint 1