Runs Test Statistic

Problem

Return the number of runs (maximal blocks of equal values) in a binary sequence. An empty sequence has 0 runs, and each change between adjacent values starts a new run.

Hint

Start counting at 1 for a nonempty sequence, then count value changes.

Test cases

case 1

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

expected: 3

case 2

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

expected: 5

case 3

in: [[]]

expected: 0

case 4

in: [[0,0,0]]

expected: 1

Starter codePython

def count_runs(sequence):
    # Your code here
    pass

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