algorithms-1/array/longest_non_repeat.py at master · githubch/algorithms-1 · GitHub

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# Given a string, find the length of the longest substring

# without repeating characters.

# Examples:

# Given "abcabcbb", the answer is "abc", which the length is 3.

# Given "bbbbb", the answer is "b", with the length of 1.

# Given "pwwkew", the answer is "wke", with the length of 3.

# Note that the answer must be a substring,

# "pwke" is a subsequence and not a substring.

def longest_non_repeat(s):

start, maxlen = 0, 0

used_char = {}

for i, char in enumerate(s):

if char in used_char and start <= used_char[char]:

start = used_char[char] + 1

else:

maxlen = max(maxlen, i-start+1)

used_char[char] = i

return maxlen

a = "abcabcdefbb"

print(a)

print(longest_non_repeat(a))

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