这是我参与8月更文挑战的第24天，活动详情查看：8月更文挑战
描述
For a string sequence, a string word is k-repeating if word concatenated k times is a substring of sequence. The word's maximum k-repeating value is the highest value k where word is k-repeating in sequence. If word is not a substring of sequence, word's maximum k-repeating value is 0.
Given strings sequence and word, return the maximum k-repeating value of word in sequence.
Example 1:
Input: sequence = "ababc", word = "ab"
Output: 2
Explanation: "abab" is a substring in "ababc".
Example 2:
Input: sequence = "ababc", word = "ba"
Output: 1
Explanation: "ba" is a substring in "ababc". "baba" is not a substring in "ababc".
Example 3:
Input: sequence = "ababc", word = "ac"
Output: 0
Explanation: "ac" is not a substring in "ababc".
Note:
1 <= sequence.length <= 100
1 <= word.length <= 100
sequence and word contains only lowercase English letters.
解析
根据题意，就是找出字符串 sequence 中最大个数的连续 word 。思路比较简单，就是先计算 word 可以连续拼接的最大次数 n ，然后将 word 拼接 n 次之后判断是否存在于 sequence 中，如果不存在那就判断 n-1 是否存在于 sequence 中，以此类推，如果都没有，那就直接返 0 即可。
解答
class Solution(object):
def maxRepeating(self, sequence, word):
"""
:type sequence: str
:type word: str
:rtype: int
"""
L = len(sequence)
l = len(word)
n = L // l
for i in range(n, 0, -1):
if sequence.count(word * i):
return i
return 0
运行结果
Runtime: 16 ms, faster than 76.23% of Python online submissions for Maximum Repeating Substring.
Memory Usage: 13.4 MB, less than 59.84% of Python online submissions for Maximum Repeating Substring.
解析
另外，可以用 python 的内置函数 find 来解决该题。基本的思想和上面的类似，就是计算出 word 可能存在于 sequence 的最大的次数，然后遍历 [1,count] 中的每个元素 n ，使用 find 函数查找 word*n 是否存在于 sequence ，如果存在则结果加一，否则直接返回 result 。
解答
class Solution(object):
def maxRepeating(self, sequence, word):
"""
:type sequence: str
:type word: str
:rtype: int
"""
result = 0
count = len(sequence) // len(word)
for n in range(1, count + 1):
if sequence.find(word * n) != -1:
result += 1
else:
break
return result
运行结果
Runtime: 8 ms, faster than 100.00% of Python online submissions for Maximum Repeating Substring.
Memory Usage: 13.6 MB, less than 34.78% of Python online submissions for Maximum Repeating Substring.
原题链接：leetcode.com/problems/ma…
您的支持是我最大的动力
