feat: update lc problems (#3310)

Author: yanglbme

lcof2/剑指 Offer II 073. 狒狒吃香蕉/README.md

@@ -189,22 +189,22 @@ class Solution {
     func minEatingSpeed(_ piles: [Int], _ h: Int) -> Int {
         var left = 1
         var right = piles.max() ?? 0
-        
+
         while left < right {
             let mid = (left + right) / 2
             var hours = 0
-            
+
             for pile in piles {
                 hours += (pile + mid - 1) / mid
             }
-            
+
             if hours <= h {
                 right = mid
             } else {
                 left = mid + 1
             }
         }
-        
+
         return left
     }
 }

solution/2000-2099/2095.Delete the Middle Node of a Linked List/README.md

@@ -81,7 +81,13 @@ tags:
 
 <!-- solution:start -->
 
-### 方法一
+### 方法一：快慢指针
+
+快慢指针法是一种用于解决链表中的问题的常用技巧。我们可以维护两个指针，一个慢指针 $\textit{slow}$ 和一个快指针 $\textit{fast}$。初始时 $\textit{slow}$ 指向一个虚拟节点，该虚拟节点的 $\textit{next}$ 指针指向链表的头节点 $\textit{head}$，而 $\textit{fast}$ 指向链表的头节点 $\textit{head}$。
+
+然后，我们每次将慢指针向后移动一个位置，将快指针向后移动两个位置，直到快指针到达链表的末尾。此时，慢指针指向的节点的下一个节点就是链表的中间节点。我们将慢指针指向的节点的 $\textit{next}$ 指针指向下下个节点，即可删除中间节点。
+
+时间复杂度 $O(n)$，其中 $n$ 是链表的长度。空间复杂度 $O(1)$。
 
 <!-- tabs:start -->
 
@@ -197,15 +203,14 @@ func deleteMiddle(head *ListNode) *ListNode {
  */
 
 function deleteMiddle(head: ListNode | null): ListNode | null {
-    if (!head || !head.next) return null;
-    let fast = head.next,
-        slow = head;
-    while (fast.next && fast.next.next) {
+    const dummy = new ListNode(0, head);
+    let [slow, fast] = [dummy, head];
+    while (fast && fast.next) {
         slow = slow.next;
         fast = fast.next.next;
     }
     slow.next = slow.next.next;
-    return head;
+    return dummy.next;
 }
 ```
 

solution/2000-2099/2095.Delete the Middle Node of a Linked List/README_EN.md

@@ -73,7 +73,13 @@ Node 0 with value 2 is the only node remaining after removing node 1.</pre>
 
 <!-- solution:start -->
 
-### Solution 1
+### Solution 1: Fast and Slow Pointers
+
+The fast and slow pointer technique is a common method used to solve problems related to linked lists. We can maintain two pointers, a slow pointer $\textit{slow}$ and a fast pointer $\textit{fast}$. Initially, $\textit{slow}$ points to a dummy node, whose $\textit{next}$ pointer points to the head node $\textit{head}$ of the list, while $\textit{fast}$ points to the head node $\textit{head}$.
+
+Then, we move the slow pointer one position backward and the fast pointer two positions backward each time, until the fast pointer reaches the end of the list. At this point, the node next to the node pointed by the slow pointer is the middle node of the list. We can remove the middle node by setting the $\textit{next}$ pointer of the node pointed by the slow pointer to point to the next next node.
+
+The time complexity is $O(n)$, where $n$ is the length of the list. The space complexity is $O(1)$.
 
 <!-- tabs:start -->
 
@@ -189,15 +195,14 @@ func deleteMiddle(head *ListNode) *ListNode {
  */
 
 function deleteMiddle(head: ListNode | null): ListNode | null {
-    if (!head || !head.next) return null;
-    let fast = head.next,
-        slow = head;
-    while (fast.next && fast.next.next) {
+    const dummy = new ListNode(0, head);
+    let [slow, fast] = [dummy, head];
+    while (fast && fast.next) {
         slow = slow.next;
         fast = fast.next.next;
     }
     slow.next = slow.next.next;
-    return head;
+    return dummy.next;
 }
 ```
 

solution/2000-2099/2095.Delete the Middle Node of a Linked List/Solution.ts

@@ -11,13 +11,12 @@
  */
 
 function deleteMiddle(head: ListNode | null): ListNode | null {
-    if (!head || !head.next) return null;
-    let fast = head.next,
-        slow = head;
-    while (fast.next && fast.next.next) {
+    const dummy = new ListNode(0, head);
+    let [slow, fast] = [dummy, head];
+    while (fast && fast.next) {
         slow = slow.next;
         fast = fast.next.next;
     }
     slow.next = slow.next.next;
-    return head;
+    return dummy.next;
 }

solution/2000-2099/2098.Subsequence of Size K With the Largest Even Sum/README.md

@@ -107,7 +107,7 @@ class Solution:
             else:
                 mi1 = x
         ans = max(ans - mi1 + mx1, ans - mi2 + mx2, -1)
-        return -1 if ans % 2 else ans
+        return -1 if ans < 0 else ans
 ```
 
 #### Java
@@ -141,8 +141,8 @@ class Solution {
                 mi1 = nums[i];
             }
         }
-        ans = Math.max(-1, Math.max(ans - mi1 + mx1, ans - mi2 + mx2));
-        return ans % 2 != 0 ? -1 : ans;
+        ans = Math.max(ans - mi1 + mx1, ans - mi2 + mx2);
+        return ans < 0 ? -1 : ans;
     }
 }
 ```
@@ -180,7 +180,7 @@ public:
             }
         }
         ans = max(ans - mi1 + mx1, ans - mi2 + mx2);
-        return ans % 2 || ans < 0 ? -1 : ans;
+        return ans < 0 ? -1 : ans;
     }
 };
 ```
@@ -216,13 +216,50 @@ func largestEvenSum(nums []int, k int) int64 {
 		}
 	}
 	ans = max(-1, max(ans-mi1+mx1, ans-mi2+mx2))
-	if ans%2 != 0 {
+	if ans%2 < 0 {
 		return -1
 	}
 	return int64(ans)
 }
 ```
 
+#### TypeScript
+
+```ts
+function largestEvenSum(nums: number[], k: number): number {
+    nums.sort((a, b) => a - b);
+    let ans = 0;
+    const n = nums.length;
+    for (let i = 0; i < k; ++i) {
+        ans += nums[n - i - 1];
+    }
+    if (ans % 2 === 0) {
+        return ans;
+    }
+    const inf = 1 << 29;
+    let mx1 = -inf,
+        mx2 = -inf;
+    for (let i = 0; i < n - k; ++i) {
+        if (nums[i] % 2 === 1) {
+            mx1 = nums[i];
+        } else {
+            mx2 = nums[i];
+        }
+    }
+    let mi1 = inf,
+        mi2 = inf;
+    for (let i = n - 1; i >= n - k; --i) {
+        if (nums[i] % 2 === 1) {
+            mi2 = nums[i];
+        } else {
+            mi1 = nums[i];
+        }
+    }
+    ans = Math.max(ans - mi1 + mx1, ans - mi2 + mx2);
+    return ans < 0 ? -1 : ans;
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/2000-2099/2098.Subsequence of Size K With the Largest Even Sum/README_EN.md

@@ -67,7 +67,20 @@ No subsequence of nums with length 1 has an even sum.
 
 <!-- solution:start -->
 
-### Solution 1
+### Solution 1: Greedy + Sorting
+
+We notice that the problem involves selecting a subsequence, so we can consider sorting the array first.
+
+Next, we greedily select the largest $k$ numbers. If the sum of these numbers is even, we directly return this sum $ans$.
+
+Otherwise, we have two greedy strategies:
+
+1. Among the largest $k$ numbers, find the smallest even number $mi1$, and then among the remaining $n - k$ numbers, find the largest odd number $mx1$. Replace $mi1$ with $mx1$. If such a replacement exists, then the sum after replacement $ans - mi1 + mx1$ is guaranteed to be even;
+2. Among the largest $k$ numbers, find the smallest odd number $mi2$, and then among the remaining $n - k$ numbers, find the largest even number $mx2$. Replace $mi2$ with $mx2$. If such a replacement exists, then the sum after replacement $ans - mi2 + mx2$ is guaranteed to be even.
+
+We take the largest even sum as the answer. If no even sum exists, return $-1$.
+
+The time complexity is $O(n \times \log n)$, and the space complexity is $O(\log n)$. Here, $n$ is the length of the array.
 
 <!-- tabs:start -->
 
@@ -94,7 +107,7 @@ class Solution:
             else:
                 mi1 = x
         ans = max(ans - mi1 + mx1, ans - mi2 + mx2, -1)
-        return -1 if ans % 2 else ans
+        return -1 if ans < 0 else ans
 ```
 
 #### Java
@@ -128,8 +141,8 @@ class Solution {
                 mi1 = nums[i];
             }
         }
-        ans = Math.max(-1, Math.max(ans - mi1 + mx1, ans - mi2 + mx2));
-        return ans % 2 != 0 ? -1 : ans;
+        ans = Math.max(ans - mi1 + mx1, ans - mi2 + mx2);
+        return ans < 0 ? -1 : ans;
     }
 }
 ```
@@ -167,7 +180,7 @@ public:
             }
         }
         ans = max(ans - mi1 + mx1, ans - mi2 + mx2);
-        return ans % 2 || ans < 0 ? -1 : ans;
+        return ans < 0 ? -1 : ans;
     }
 };
 ```
@@ -203,13 +216,50 @@ func largestEvenSum(nums []int, k int) int64 {
 		}
 	}
 	ans = max(-1, max(ans-mi1+mx1, ans-mi2+mx2))
-	if ans%2 != 0 {
+	if ans%2 < 0 {
 		return -1
 	}
 	return int64(ans)
 }
 ```
 
+#### TypeScript
+
+```ts
+function largestEvenSum(nums: number[], k: number): number {
+    nums.sort((a, b) => a - b);
+    let ans = 0;
+    const n = nums.length;
+    for (let i = 0; i < k; ++i) {
+        ans += nums[n - i - 1];
+    }
+    if (ans % 2 === 0) {
+        return ans;
+    }
+    const inf = 1 << 29;
+    let mx1 = -inf,
+        mx2 = -inf;
+    for (let i = 0; i < n - k; ++i) {
+        if (nums[i] % 2 === 1) {
+            mx1 = nums[i];
+        } else {
+            mx2 = nums[i];
+        }
+    }
+    let mi1 = inf,
+        mi2 = inf;
+    for (let i = n - 1; i >= n - k; --i) {
+        if (nums[i] % 2 === 1) {
+            mi2 = nums[i];
+        } else {
+            mi1 = nums[i];
+        }
+    }
+    ans = Math.max(ans - mi1 + mx1, ans - mi2 + mx2);
+    return ans < 0 ? -1 : ans;
+}
+```
+
 <!-- tabs:end -->
 
 <!-- solution:end -->

solution/2000-2099/2098.Subsequence of Size K With the Largest Even Sum/Solution.cpp

@@ -28,6 +28,6 @@ class Solution {
             }
         }
         ans = max(ans - mi1 + mx1, ans - mi2 + mx2);
-        return ans % 2 || ans < 0 ? -1 : ans;
+        return ans < 0 ? -1 : ans;
     }
 };

solution/2000-2099/2098.Subsequence of Size K With the Largest Even Sum/Solution.go

@@ -26,7 +26,7 @@ func largestEvenSum(nums []int, k int) int64 {
 		}
 	}
 	ans = max(-1, max(ans-mi1+mx1, ans-mi2+mx2))
-	if ans%2 != 0 {
+	if ans%2 < 0 {
 		return -1
 	}
 	return int64(ans)

solution/2000-2099/2098.Subsequence of Size K With the Largest Even Sum/Solution.java

@@ -26,7 +26,7 @@ public long largestEvenSum(int[] nums, int k) {
                 mi1 = nums[i];
             }
         }
-        ans = Math.max(-1, Math.max(ans - mi1 + mx1, ans - mi2 + mx2));
-        return ans % 2 != 0 ? -1 : ans;
+        ans = Math.max(ans - mi1 + mx1, ans - mi2 + mx2);
+        return ans < 0 ? -1 : ans;
     }
 }

solution/2000-2099/2098.Subsequence of Size K With the Largest Even Sum/Solution.py

@@ -18,4 +18,4 @@ def largestEvenSum(self, nums: List[int], k: int) -> int:
             else:
                 mi1 = x
         ans = max(ans - mi1 + mx1, ans - mi2 + mx2, -1)
-        return -1 if ans % 2 else ans
+        return -1 if ans < 0 else ans