Grokking the Coding Interview: Patterns for Coding Questions

Solution: All Tasks Scheduling Orders

## Problem Statement

There are ‘N’ tasks, labeled from ‘0’ to ‘N-1’. Each task can have some prerequisite tasks which need to be completed before it can be scheduled. 

Given the number of tasks and a list of prerequisite pairs, write a method to print all possible ordering of tasks meeting all prerequisites.

### Examples

**Example 1**:
```
Input: Tasks=4, Prerequisites=[3, 2], [3, 0], [2, 0], [2, 1]
Output: 
1) [3, 2, 0, 1]
2) [3, 2, 1, 0]
Explanation: There are two possible orderings of the tasks meeting all prerequisites.
```

**Example 2**:
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