From 9fb6195c4cc90c0ec525e7c601d17633ab00cee4 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=BA=AA=E9=A3=9E?= Date: Tue, 18 May 2021 10:43:43 +0800 Subject: [PATCH 1/5] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=E2=80=9C1.=E4=B8=A4?= =?UTF-8?q?=E6=95=B0=E4=B9=8B=E5=92=8C=E2=80=9Djavascript=E7=89=88?= =?UTF-8?q?=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0001.两数之和.md | 19 +++++++++++++++++-- 1 file changed, 17 insertions(+), 2 deletions(-) diff --git a/problems/0001.两数之和.md b/problems/0001.两数之和.md index 21f798a9..c1759c8c 100644 --- a/problems/0001.两数之和.md +++ b/problems/0001.两数之和.md @@ -37,9 +37,9 @@ https://leetcode-cn.com/problems/two-sum/ 本题呢，则要使用map，那么来看一下使用数组和set来做哈希法的局限。 * 数组的大小是受限制的，而且如果元素很少，而哈希值太大会造成内存空间的浪费。 -* set是一个集合，里面放的元素只能是一个key，而两数之和这道题目，不仅要判断y是否存在而且还要记录y的下表位置，因为要返回x 和 y的下表。所以set 也不能用。 +* set是一个集合，里面放的元素只能是一个key，而两数之和这道题目，不仅要判断y是否存在而且还要记录y的下标位置，因为要返回x 和 y的下标。所以set 也不能用。 -此时就要选择另一种数据结构：map ，map是一种key value的存储结构，可以用key保存数值，用value在保存数值所在的下表。 +此时就要选择另一种数据结构：map ，map是一种key value的存储结构，可以用key保存数值，用value在保存数值所在的下标。 C++中map，有三种类型： @@ -156,6 +156,21 @@ impl Solution { } ``` +Javascript + +```javascript +var twoSum = function (nums, target) { + let hash = {}; + for (let i = 0; i < nums.length; i++) { + if (hash[target - nums[i]] !== undefined) { + return [i, hash[target - nums[i]]]; + } + hash[nums[i]] = i; + } + return []; +}; +``` + From a811e9aa69e421fe788d9f5923bfdb07b1083e00 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=BA=AA=E9=A3=9E?= Date: Tue, 18 May 2021 12:30:08 +0800 Subject: [PATCH 2/5] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=E2=80=9C20.=E6=9C=89?= =?UTF-8?q?=E6=95=88=E7=9A=84=E6=8B=AC=E5=8F=B7=E2=80=9DJavascript?= =?UTF-8?q?=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0020.有效的括号.md | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+) diff --git a/problems/0020.有效的括号.md b/problems/0020.有效的括号.md index 98cc7cd8..6c630f39 100644 --- a/problems/0020.有效的括号.md +++ b/problems/0020.有效的括号.md @@ -247,6 +247,32 @@ def is_valid(strs) end ``` +Javascript: +```javascript +var isValid = function (s) { + const stack = []; + for (let i = 0; i < s.length; i++) { + let c = s[i]; + switch (c) { + case '(': + stack.push(')'); + break; + case '[': + stack.push(']'); + break; + case '{': + stack.push('}'); + break; + default: + if (c !== stack.pop()) { + return false; + } + } + } + return stack.length === 0; +}; +``` + ----------------------- * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw) From 3c5ed1ebae1a0766f27797182d69c33238251995 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=BA=AA=E9=A3=9E?= Date: Tue, 18 May 2021 12:30:49 +0800 Subject: [PATCH 3/5] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=E2=80=9C24.=E4=B8=A4?= =?UTF-8?q?=E4=B8=A4=E4=BA=A4=E6=8D=A2=E9=93=BE=E8=A1=A8=E4=B8=AD=E7=9A=84?= =?UTF-8?q?=E8=8A=82=E7=82=B9=E2=80=9DJavascript=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0024.两两交换链表中的节点.md | 15 +++++++++++++++ 1 file changed, 15 insertions(+) diff --git a/problems/0024.两两交换链表中的节点.md b/problems/0024.两两交换链表中的节点.md index 132d65bb..bda64da6 100644 --- a/problems/0024.两两交换链表中的节点.md +++ b/problems/0024.两两交换链表中的节点.md @@ -132,6 +132,21 @@ Python： Go： +Javascript: +```javascript +var swapPairs = function (head) { + let ret = new ListNode(0, head), temp = ret; + while (temp.next && temp.next.next) { + let cur = temp.next.next, pre = temp.next; + pre.next = cur.next; + cur.next = pre; + temp.next = cur; + temp = pre; + } + return ret.next; +}; +``` + ----------------------- * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw) From 4417f180dd0a77ce850ec236a2b430d8e185870b Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=BA=AA=E9=A3=9E?= Date: Tue, 18 May 2021 12:35:01 +0800 Subject: [PATCH 4/5] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=20=E2=80=9C102.=E4=BA=8C?= =?UTF-8?q?=E5=8F=89=E6=A0=91=E7=9A=84=E5=B1=82=E5=BA=8F=E9=81=8D=E5=8E=86?= =?UTF-8?q?=E2=80=9DJavascript=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0102.二叉树的层序遍历.md | 20 ++++++++++++++++++++ 1 file changed, 20 insertions(+) diff --git a/problems/0102.二叉树的层序遍历.md b/problems/0102.二叉树的层序遍历.md index 0ab67b13..1cb4164f 100644 --- a/problems/0102.二叉树的层序遍历.md +++ b/problems/0102.二叉树的层序遍历.md @@ -687,6 +687,26 @@ func levelOrder(root *TreeNode) [][]int { return result } ``` +Javascript: +```javascript +var levelOrder = function (root) { + let ans = []; + if (!root) return ans; + let queue = [root]; + while (queue.length) { + let size = queue.length; + let temp = []; + while (size--) { + let n = queue.shift(); + temp.push(n.val); + if (n.left) queue.push(n.left); + if (n.right) queue.push(n.right); + } + ans.push(temp); + } + return ans; +}; +``` ----------------------- * 作者微信：[程序员Carl](https://mp.weixin.qq.com/s/b66DFkOp8OOxdZC_xLZxfw) From 55cfb394f78b66f5063df07ba7669dde3ff15e90 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?=E7=BA=AA=E9=A3=9E?= Date: Tue, 18 May 2021 12:50:29 +0800 Subject: [PATCH 5/5] =?UTF-8?q?=E6=B7=BB=E5=8A=A0=E2=80=9C239.=E6=BB=91?= =?UTF-8?q?=E5=8A=A8=E7=AA=97=E5=8F=A3=E6=9C=80=E5=A4=A7=E5=80=BC=E2=80=9D?= =?UTF-8?q?Javascript=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- problems/0239.滑动窗口最大值.md | 25 ++++++++++++++++++++++++- 1 file changed, 24 insertions(+), 1 deletion(-) diff --git a/problems/0239.滑动窗口最大值.md b/problems/0239.滑动窗口最大值.md index 781bfa6f..7d0a145f 100644 --- a/problems/0239.滑动窗口最大值.md +++ b/problems/0239.滑动窗口最大值.md @@ -267,7 +267,30 @@ Python： Go： - +Javascript: +```javascript +var maxSlidingWindow = function (nums, k) { + // 队列数组（存放的是元素下标，为了取值方便） + const q = []; + // 结果数组 + const ans = []; + for (let i = 0; i < nums.length; i++) { + // 若队列不为空，且当前元素大于等于队尾所存下标的元素，则弹出队尾 + while (q.length && nums[i] >= nums[q[q.length - 1]]) { + q.pop(); + } + // 入队当前元素下标 + q.push(i); + // 判断当前最大值（即队首元素）是否在窗口中，若不在便将其出队 + while (q[0] <= i - k) { + q.shift(); + } + // 当达到窗口大小时便开始向结果中添加数据 + if (i >= k - 1) ans.push(nums[q[0]]); + } + return ans; +}; +``` -----------------------