From ffe981fb6c5af5c7400f3b82c455b80ac8333fc0 Mon Sep 17 00:00:00 2001 From: AronJudge <2286381138@qq.com> Date: Sun, 26 Jun 2022 23:50:32 +0800 Subject: [PATCH 1/4] =?UTF-8?q?0977.=20=E6=9C=89=E5=BA=8F=E6=95=B0?= =?UTF-8?q?=E7=BB=84=E7=9A=84=E5=B9=B3=E6=96=B9=20=E6=B7=BB=E5=8A=A0Java?= =?UTF-8?q?=E6=B3=A8=E9=87=8A?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0977.有序数组的平方.md | 1 + 1 file changed, 1 insertion(+) diff --git a/problems/0977.有序数组的平方.md b/problems/0977.有序数组的平方.md index 20bdf7b0..d274d778 100644 --- a/problems/0977.有序数组的平方.md +++ b/problems/0977.有序数组的平方.md @@ -106,6 +106,7 @@ class Solution { int index = result.length - 1; while (left <= right) { if (nums[left] * nums[left] > nums[right] * nums[right]) { + // 正数的相对位置是不变的， 需要调整的是负数平方后的相对位置 result[index--] = nums[left] * nums[left]; ++left; } else { From 11b701fdb6ba689bdc9f07362e497a4d2ab5eefd Mon Sep 17 00:00:00 2001 From: AronJudge <2286381138@qq.com> Date: Mon, 4 Jul 2022 00:58:56 +0800 Subject: [PATCH 2/4] =?UTF-8?q?0018=20Java=E4=BB=A3=E7=A0=81=E9=83=A8?= =?UTF-8?q?=E5=88=86=E5=A2=9E=E5=8A=A0=E5=89=AA=E6=9E=9D=E6=93=8D=E4=BD=9C?= =?UTF-8?q?,=E4=B8=8D=E7=84=B6Leetcode=E4=B8=8D=E8=83=BD=E9=80=9A=E8=BF=87?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0018.四数之和.md | 5 +++++ 1 file changed, 5 insertions(+) diff --git a/problems/0018.四数之和.md b/problems/0018.四数之和.md index 6cbd40c2..d0b7fc68 100644 --- a/problems/0018.四数之和.md +++ b/problems/0018.四数之和.md @@ -140,6 +140,11 @@ class Solution { for (int i = 0; i < nums.length; i++) { + // nums[i] > target 直接返回, 剪枝操作 + if (nums[i] > 0 && nums[i] > target) { + return result; + } + if (i > 0 && nums[i - 1] == nums[i]) { continue; } From 85e0d6c85d593339152483a3fea33ab23cdcd5b3 Mon Sep 17 00:00:00 2001 From: AronJudge <2286381138@qq.com> Date: Mon, 11 Jul 2022 11:06:51 +0800 Subject: [PATCH 3/4] =?UTF-8?q?=E6=9B=B4=E6=96=B00347=20=E5=89=8DK?= =?UTF-8?q?=E4=B8=AA=E9=AB=98=E9=A2=91=E5=85=83=E7=B4=A0?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 由原来的构建小顶堆改为构建大顶堆，减少部分代码逻辑，并增加了注释 通过LeetCode提交代码，修改后的执行时间更快。 --- problems/0347.前K个高频元素.md | 7 ++----- 1 file changed, 2 insertions(+), 5 deletions(-) diff --git a/problems/0347.前K个高频元素.md b/problems/0347.前K个高频元素.md index a04041cc..0c978b2a 100644 --- a/problems/0347.前K个高频元素.md +++ b/problems/0347.前K个高频元素.md @@ -141,13 +141,10 @@ class Solution { } Set> entries = map.entrySet(); - // 根据map的value值正序排，相当于一个小顶堆 - PriorityQueue> queue = new PriorityQueue<>((o1, o2) -> o1.getValue() - o2.getValue()); + // 根据map的value值，构建于一个大顶堆（o1 - o2: 小顶堆， o2 - o1 : 大顶堆） + PriorityQueue> queue = new PriorityQueue<>((o1, o2) -> o2.getValue() - o1.getValue()); for (Map.Entry entry : entries) { queue.offer(entry); - if (queue.size() > k) { - queue.poll(); - } } for (int i = k - 1; i >= 0; i--) { result[i] = queue.poll().getKey(); From ba081f84a85ff75134c4db551e0e631b86693081 Mon Sep 17 00:00:00 2001 From: AronJudge <2286381138@qq.com> Date: Tue, 12 Jul 2022 11:36:26 +0800 Subject: [PATCH 4/4] =?UTF-8?q?=E6=9B=B4=E6=96=B0=200104.=20=E4=BA=8C?= =?UTF-8?q?=E5=8F=89=E6=A0=91=E6=9C=80=E5=A4=A7=E6=B7=B1=E5=BA=A6?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 代码错误，更正代码，通过LeetCode代码检验。 --- problems/0104.二叉树的最大深度.md | 25 +++++++++++------------ 1 file changed, 12 insertions(+), 13 deletions(-) diff --git a/problems/0104.二叉树的最大深度.md b/problems/0104.二叉树的最大深度.md index ed27f95d..55980189 100644 --- a/problems/0104.二叉树的最大深度.md +++ b/problems/0104.二叉树的最大深度.md @@ -294,14 +294,13 @@ class solution { /** * 递归法 */ - public int maxdepth(treenode root) { + public int maxDepth(TreeNode root) { if (root == null) { return 0; } - int leftdepth = maxdepth(root.left); - int rightdepth = maxdepth(root.right); - return math.max(leftdepth, rightdepth) + 1; - + int leftDepth = maxDepth(root.left); + int rightDepth = maxDepth(root.right); + return Math.max(leftDepth, rightDepth) + 1; } } ``` @@ -311,23 +310,23 @@ class solution { /** * 迭代法，使用层序遍历 */ - public int maxdepth(treenode root) { + public int maxDepth(TreeNode root) { if(root == null) { return 0; } - deque deque = new linkedlist<>(); + Deque deque = new LinkedList<>(); deque.offer(root); int depth = 0; - while (!deque.isempty()) { + while (!deque.isEmpty()) { int size = deque.size(); depth++; for (int i = 0; i < size; i++) { - treenode poll = deque.poll(); - if (poll.left != null) { - deque.offer(poll.left); + TreeNode node = deque.poll(); + if (node.left != null) { + deque.offer(node.left); } - if (poll.right != null) { - deque.offer(poll.right); + if (node.right != null) { + deque.offer(node.right); } } }