Z algorithm
(String/z_algorithm.py)

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• Last update: 2021-01-05 22:30:17+09:00

使い方

z_algorithm(s: Sequence[Any]) -> List[int]
s と s[i:] の共通接頭辞の長さを格納した長さ n = len(s) の配列を返す。計算量 $O(n)$

Verified with

• TestCase/LibraryChecker/zalgorithm.test.py

Code

def z_algorithm(s):
    res = [0] * len(s)
    res[0] = len(s)
    i, j = 1, 0
    while i < len(s):
        while i + j < len(s) and s[j] == s[i + j]:
            j += 1
        res[i] = j
        if j == 0:
            i += 1
            continue
        k = 1
        while i + k < len(s) and k + res[k] < j:
            res[i + k] = res[k]
            k += 1
        i, j = i + k, j - k
    return res

Traceback (most recent call last):
  File "/opt/hostedtoolcache/Python/3.12.4/x64/lib/python3.12/site-packages/onlinejudge_verify/documentation/build.py", line 71, in _render_source_code_stat
    bundled_code = language.bundle(stat.path, basedir=basedir, options={'include_paths': [basedir]}).decode()
                   ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "/opt/hostedtoolcache/Python/3.12.4/x64/lib/python3.12/site-packages/onlinejudge_verify/languages/python.py", line 96, in bundle
    raise NotImplementedError
NotImplementedError

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