From 31e340bf6c953850705bf80701f7f9df5c6622d6 Mon Sep 17 00:00:00 2001 From: Jack_ZhijieFang <56966563+laerpeeK@users.noreply.github.com> Date: Fri, 5 Aug 2022 02:45:36 +0800 Subject: [PATCH 1/4] =?UTF-8?q?fix:=E9=93=BE=E8=A1=A8=E7=90=86=E8=AE=BA?= =?UTF-8?q?=E5=9F=BA=E7=A1=80.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit typescript中,null只能赋值给any和null类型变量。这里需要采用联合类型声明。 --- problems/链表理论基础.md | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/problems/链表理论基础.md b/problems/链表理论基础.md index 1a29c32a..8378f7f2 100644 --- a/problems/链表理论基础.md +++ b/problems/链表理论基础.md @@ -186,7 +186,7 @@ TypeScript: ```typescript class ListNode { public val: number; - public next: ListNode = null; + public next: ListNode|null = null; constructor(value: number) { this.val = value; this.next = null; From 0f96289ed1485f64b010864c1ee26bd94051c132 Mon Sep 17 00:00:00 2001 From: Jack_ZhijieFang <56966563+laerpeeK@users.noreply.github.com> Date: Fri, 5 Aug 2022 03:15:03 +0800 Subject: [PATCH 2/4] =?UTF-8?q?fix=200203.=E7=A7=BB=E9=99=A4=E9=93=BE?= =?UTF-8?q?=E8=A1=A8=E5=85=83=E7=B4=A0.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 修复某个变量编译时的类型问题。 --- problems/0203.移除链表元素.md | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/problems/0203.移除链表元素.md b/problems/0203.移除链表元素.md index 6fd9b66f..5622fd1c 100644 --- a/problems/0203.移除链表元素.md +++ b/problems/0203.移除链表元素.md @@ -385,7 +385,8 @@ function removeElements(head: ListNode | null, val: number): ListNode | null { if (cur.val === val) { pre.next = cur.next; } else { - pre = pre.next; + //此处不加类型断言时:编译器会认为pre类型为ListNode, pre.next类型为ListNode | null + pre = pre.next as ListNode; } cur = cur.next; } From 5868d5ec6dfd786c32cb6485e96fd861b28fccf2 Mon Sep 17 00:00:00 2001 From: Jack_ZhijieFang <56966563+laerpeeK@users.noreply.github.com> Date: Sun, 7 Aug 2022 02:11:01 +0800 Subject: [PATCH 3/4] =?UTF-8?q?Update=200019.=E5=88=A0=E9=99=A4=E9=93=BE?= =?UTF-8?q?=E8=A1=A8=E7=9A=84=E5=80=92=E6=95=B0=E7=AC=ACN=E4=B8=AA?= =?UTF-8?q?=E8=8A=82=E7=82=B9.md?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 原方法编译时发现对节点类型缺少断言。 --- ...0019.删除链表的倒数第N个节点.md | 20 ++++++++++--------- 1 file changed, 11 insertions(+), 9 deletions(-) diff --git a/problems/0019.删除链表的倒数第N个节点.md b/problems/0019.删除链表的倒数第N个节点.md index 3499ab9d..62fe4f8b 100644 --- a/problems/0019.删除链表的倒数第N个节点.md +++ b/problems/0019.删除链表的倒数第N个节点.md @@ -188,18 +188,20 @@ TypeScript: ```typescript function removeNthFromEnd(head: ListNode | null, n: number): ListNode | null { let newHead: ListNode | null = new ListNode(0, head); - let slowNode: ListNode | null = newHead, - fastNode: ListNode | null = newHead; - for (let i = 0; i < n; i++) { - fastNode = fastNode.next; + //根据leetcode题目的定义可推断这里快慢指针均不需要定义为ListNode | null。 + let slowNode: ListNode = newHead; + let fastNode: ListNode = newHead; + + while(n--) { + fastNode = fastNode.next!; //由虚拟头节点前进n个节点时,fastNode.next可推断不为null。 } - while (fastNode.next) { + while(fastNode.next) { //遍历直至fastNode.next = null, 即尾部节点。 此时slowNode指向倒数第n个节点。 fastNode = fastNode.next; - slowNode = slowNode.next; + slowNode = slowNode.next!; } - slowNode.next = slowNode.next.next; - return newHead.next; -}; + slowNode.next = slowNode.next!.next; //倒数第n个节点可推断其next节点不为空。 + return newHead.next; +} ``` 版本二(计算节点总数法): From 736ae6a2076393b97555ed14fa299e8f656adc33 Mon Sep 17 00:00:00 2001 From: Jack_ZhijieFang <56966563+laerpeeK@users.noreply.github.com> Date: Thu, 18 Aug 2022 15:16:59 +0800 Subject: [PATCH 4/4] =?UTF-8?q?Update=200015.=E4=B8=89=E6=95=B0=E4=B9=8B?= =?UTF-8?q?=E5=92=8C.md=20typescript=E7=89=88=E6=9C=AC?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit Update 0015.三数之和.md typescript版本。添加提前跳出循环判断条件。 --- problems/0015.三数之和.md | 3 +++ 1 file changed, 3 insertions(+) diff --git a/problems/0015.三数之和.md b/problems/0015.三数之和.md index da319866..a4b6b84d 100644 --- a/problems/0015.三数之和.md +++ b/problems/0015.三数之和.md @@ -493,6 +493,9 @@ function threeSum(nums: number[]): number[][] { right: number = length - 1; let resArr: number[][] = []; for (let i = 0; i < length; i++) { + if (nums[i]>0) { + return resArr; //nums经过排序后,只要nums[i]>0, 此后的nums[i] + nums[left] + nums[right]均大于0,可以提前终止循环。 + } if (i > 0 && nums[i] === nums[i - 1]) { continue; }