摘要： Determine if a Sudoku is valid, according to: Sudoku Puzzles - The Rules.The Sudoku board could be partially filled, where empty cells are filled with... 阅读全文

摘要： Given a linked list, remove the nth node from the end of list and return its head.For example,Given linked list: 1->2->3->4->5, and n = 2. After remov... 阅读全文

摘要： Given a linked list and a value x, partition it such that all nodes less than x come before nodes greater than or equal to x.You should preserve the o... 阅读全文