无重复字符的最长字母

给定一个字符串，请你找出其中不含有重复字符串的最长子串的长度

s = input()
dict = {}
max_start = 0
max_end = 0
start = 0
for i in range(len(s)):
    if s[i] in dict.keys() and (dict[s[i]] + 1) > start:
        start = dict[s[i]] + 1
    if i - start > (max_end - max_start):
        max_start = start
        max_end = i
    dict[s[i]] = i
print(max_end-max_start+1, s[max_start:max_end+1])