# Course Schedule

Easy
0/40
Average time to solve is 15m

## Problem statement

You are a student of Netaji Subhas Institute of Technology. You have to take ‘N’ number of courses labelled from 1 to N to complete your B.Tech Degree.

Some courses may have prerequisites, for example, to take course 1 you have to first take course 2, which is expressed as a pair: [1, 2]. Now, your task is to find is it possible for you to finish all courses.

Note: There are no duplicate pairs in the prerequisites array.

For example-
``````If N = 2 and prerequisite = [[1, 2]]. Then, there are a total of 2 courses you need to take. To take course 1 you need to finish course 2. So, it is possible to complete all courses.
``````
Detailed explanation ( Input/output format, Notes, Images )
Constraints:
``````1 <= T <= 10
1 <= N <= 5000
0 <= M <= min(5000, (N * (N - 1)) / 2)
1 <= prerequisites[i][0] <= N
1 <= prerequisites[i][1] <= N

Time Limit: 1 sec
``````
##### Sample Input 1:
``````1
3 2
1 2
2 1
``````
##### Sample output 1:
``````No
``````
##### Explanation of Sample output 1:
``````There are a total of 3 courses you need to take. To take course 1 you need to finish course 2. To take course 2 you need to finish course 1. So, it is impossible to complete all courses.
``````
##### Sample Input 2:
``````2
4 0
4 2
1 2
2 3
``````
##### Sample output 2:
``````Yes
Yes
``````
Console