# 210. Course Schedule II

## Description

There are a total of n courses you have to take, labeled from 0 to `n - 1`

.

Some courses may have prerequisites, for example to take course 0 you have to first take course 1, which is expressed as a pair: [0,1]

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# Category: Leetcode

## Leetcode 210. Course Schedule II

# 210. Course Schedule II

## Description

## Leetcode Some problems about Binary Search Tree

# 173. Binary Search Tree Iterator

## Description

## Leetcode No.78&90 Subsets

# 78. Subsets

## Description

## Leetcode No.48 Rotate Image

# Description

SY -> CS -> LA -> SEA

There are a total of n courses you have to take, labeled from 0 to `n - 1`

.

Some courses may have prerequisites, for example to take course 0 you have to first take course 1, which is expressed as a pair: [0,1]

Implement an iterator over a binary search tree (BST). Your iterator will be initialized with the root node of a BST.

Continue reading “Leetcode Some problems about Binary Search Tree”

There are to algorithm problem about backtracking.

Given a set of distinct integers, nums, return all possible subsets.

Note: The solution set must not contain duplicate subsets.

You are given an n x n 2D matrix representing an image.

Rotate the image by 90 degrees (clockwise).

Follow up:

Could you do this in-place?