Precedence Constraints Check

Problem

Check whether a proposed task order satisfies all precedence constraints.

Each constraint [a, b] means task a must appear before task b in order. Return False when a task is missing from order or when some constraint is violated. order is a permutation of task labels.

Hint

Map each task to its position once, then compare positions for every constraint.

Test cases

case 1

in: [[0,1,2],[[0,1],[1,2]]]

expected: true

case 2

in: [[2,1,0],[[0,1]]]

expected: false

case 3

in: [[1,0],[]]

expected: true

case 4

in: [[0,1],[[0,1],[1,0]]]

expected: false

case 5

in: [[1,2,0],[[0,2]]]

expected: false

Starter codePython

def precedence_feasible(order, constraints):
    # Your code here
    pass

5 test cases · run your code against them in the editor