Amazon Written Test May 2019 Software Development Engineer I

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]

Given the total number of courses and a list of prerequisite pairs, is it possible for you to finish all courses?

Examples:
Input: 2,
[1, 0]
Output: true

Explanation: There are a total of 2 courses to take.
To take course 1 you should have finished course 0. So it is possible.
Input: 2, [[1, 0], [0, 1]]
Output: false
Explanation: There are a total of 2 courses to take.
To take course 1 you should have finished course 0, and to take course 0 you should also have finished course 1. So it is impossible.