题目传送:https://leetcode.cn/problems/binary-tree-inorder-traversal/ 运行效率: 代码如下: /返回中序遍历结果@paramroot@return///递归解法publicList<Integer>inorderTraversal(TreeNoderoot){List<Integer>result=newArrayList<>();//处理边界情况if(rootnull){returnresult;}List<Integer>leftList=inorderTrave...
题目传送:https://leetcode.cn/problems/single-number-ii/ 运行效率: 代码如下: classSolution{publicintsingleNumber(int[]nums){//直接根据公式来int((3sum(set(nums))-sum(nums))/2)HashSet<Integer>set=newHashSet<>();//用long类型的意义是为了避免数溢出longsumOfSet=0;longtotal=0;for(inti:nums){if(set.add(i)){sumOfSet+=i;...
题目传送:https://leetcode.cn/problems/binary-tree-preorder-traversal/ 运行效率: 代码如下: classSolution{publicList<Integer>preorderTraversal(TreeNoderoot){List<Integer>result=newArrayList<>();//处理边界情况if(rootnull){returnresult;}//先访问根节点result.add(root.val);//再访问左子树List<Integer>l...