Online Python Compiler

from collections import defaultdict, Counter def solve(n, edges, labels): E = defaultdict(set) for f,t in edges: E[f].add(t) E[t].add(f) N = {i:e for i,e in enumerate(labels)} R = [0]*n def r(ni): C = Counter() for e in E[ni]: E[e].remove(ni) C.update(r(e)) C.update((N[ni])) R[ni] = C[N[ni]] return C r(0) return R n = 5 edges = [[0,1],[0,2],[1,3],[0,4]] labels = "ccaca" print(solve(n, edges, labels))