Algorithm design, implement an algorithm for a directed graph -

i found interesting question related algorithm design, wasn't able solve properly.

given directed graph g = (v,e), uses adjancency lists, , integer k < |v|, implement linear-time-complexity algorithm ( o(n) ) , check if graph g has @ least k vertexes same indegree number.
suppose n == |v| + |e|

it enough pass through edges, or through edge in-nodes, , maintain number of vertices possible indegrees.

sketch of method in pyhon style:

def check(graph, k):   # each vertex count indegree   indegrees = [0] * graph.number_of_nodes()   # 'maps' number of vertices indegree   num_with_indegree = [graph.number_of_nodes()] + [0] * (graph.number_of_nodes()-2)   # pass through edge innodes.   # iteration easy implement adjancency list graph implementation.   in_node in graph.in_nodes():     # increase indegree node     indegrees[in_node] += 1     # 'move' vertex it's indegree bucket     indegree = indegrees[in_node]     num_with_indegree[indegree-1] -= 1     num_with_indegree[indegree] += 1   # returns true if bucket has @ least k vertices   return any(n >= k n in num_with_indegree)