Know the depth of a dictionary

Question

Supposing we have this dict:

d = {\'a\':1, \'b\': {\'c\':{}}}

What would be the most straightforward way of knowing the nesting depth

Answer 1

Iterative solution:

from collections import deque


def depth(d):
    q = deque([d])
    q2 = deque()
    max_depth = 0
    while q:
        curr_dict = q.popleft()
        if isinstance(curr_dict, dict):
            for di in curr_dict.itervalues():
                q2.append(di)
        if not q:
            q, q2 = q2, q
            max_depth += 1
    return max_depth

print depth(None)
print depth({})
print depth({"a": "b"})
print depth({"a": "b", "c": {"d": "e"}, "f": {"g": "h"}, "i": {"j": "k"}, "x": {}, "z": {} })
print depth({'a':1, 'b': {'c':{}}})
print depth({'foo': {'bar': {'baz': 0}, 'spam': {'ham': {'monty': 1}, 'eric': 'idle'}}, 'john': 'cleese'})