Butterfly Network Capacity

Problem

Return the multicast capacity of the symmetric butterfly network when each link has capacity link_capacity. Each receiver has two edge-disjoint paths, so network coding achieves 2 * link_capacity while plain routing only achieves link_capacity.

Hint

The middle link is coded so both receivers benefit from a single transmission.

Test cases

case 1

in: [1]

expected: 2

case 2

in: [0]

expected: 0

case 3

in: [0.5]

expected: 1

case 4

in: [10]

expected: 20

Starter codePython

def butterfly_capacity(link_capacity):
    # Your code here
    pass

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