問題 leetcode.com s = "3[a]2[bc]", return "aaabcbc". s = "3[a2[c]]", return "accaccacc". s = "2[abc]3[cd]ef", return "abcabccdcdcdef". このように[]で囲まれた文字を直前の数字の数だけ繰り返しながら文字列を作って行く問題。 解法 これはStackを…

Problem https://leetcode.com/problems/binary-tree-longest-consecutive-sequence/ How to Solve This problem is classified into Tree and can be solve by using DFS(Depth First Search). Depth First Search Firstly, I thought the only search by D…

Problem https://leetcode.com/problems/zigzag-iterator/ How to Solve By using Iterator and Queue, I can solve this problem. Iterator ListIterator (Java Platform SE 8 ) An iterator for lists that allows the programmer to traverse the list in…