计算相距最远的两个相等元素

python

from collections import Counter
from collections import defaultdict

def solution(A):
    c = Counter(A)
    repeat = [i for i in c if c[i] > 1]
    ddict = defaultdict(list)
    for i in range(len(A)):
        ddict[A[i]].append(i)
    dis = [max(ddict[i]) -  min(ddict[i]) for i in ddict if len(ddict[i]) > 1]
    return max(dis)