# 归档 2017年9月17日

## LeetCode Weekly Contest 50解题报告 作者是 在线疯狂 发布于 2017年9月17日 在 LeetCode.

LeetCode Weekly Contest 50是LeetCode举办的第五十三场正式周赛，共4道题目，比赛时长1.5小时。

LeetCode 680. Valid Palindrome II

LeetCode 677. Map Sum Pairs

LeetCode 678. Valid Parenthesis String

LeetCode 679. 24 Game

## 题目描述：

LeetCode 679. 24 Game

You have 4 cards each containing a number from 1 to 9. You need to judge whether they could operated through `*`, `/`, `+`, `-`, `(`, `)` to get the value of 24.

Example 1:

```Input: [4, 1, 8, 7]
Output ...```

## 题目描述：

LeetCode 678. Valid Parenthesis String

Given a string containing only three types of characters: '(', ')' and '*', write a function to check whether this string is valid. We define the validity of a string by ...

## 题目描述：

LeetCode 677. Map Sum Pairs

Implement a MapSum class with `insert`, and `sum` methods.

For the method `insert`, you'll be given a pair of (string, integer). The string represents the key and the integer represents the value. If the ...

## 题目描述：

LeetCode 680. Valid Palindrome II

Given a non-empty string `s`, you may delete at most one character. Judge whether you can make it a palindrome.

Example 1:

```Input: "aba"
Output: True
```

Example 2:

```Input: "abca"
Output: True
Explanation: You ...```