# 类别归档：LeetCode

LeetCode OJ is a platform for preparing technical coding interviews.

## 题目描述：

LeetCode 114. Flatten Binary Tree to Linked List

Given a binary tree, flatten it to a linked list in-place.

For example,
Given

```         1
/ \
2   5
/ \   \
3   4   6
```

The flattened tree should look like:

```   1
\
2
\
3
\
4
\
5 ...```

## LeetCode Weekly Contest 2解题报告 作者是 在线疯狂 发布于 2016年8月28日 在 LeetCode.

LeetCode Weekly Contest 2是LeetCode举办的第一场正式周赛，共3道题目，比赛时长2.5小时。

LeetCode 389. Find the Difference

LeetCode 390. Elimination Game

LeetCode 391. Perfect Rectangle

## 题目描述：

LeetCode 391. Perfect Rectangle

Given N axis-aligned rectangles where N > 0, determine if they all together form an exact cover of a rectangular region.

Each rectangle is represented as a bottom-left point and a top-right point. For example ...

## 题目描述：

LeetCode 390. Elimination Game

There is a list of sorted integers from 1 to n. Starting from left to right, remove the first number and every other number afterward until you reach the end of the list.

Repeat the ...

## 题目描述：

LeetCode 389. Find the Difference

Given two strings s and t which consist of only lowercase letters.

String t is generated by random shuffling string s and then add one more letter at a random position.

Find the letter ...