57 lines
958 B
Markdown
57 lines
958 B
Markdown
---
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layout: page
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title: Implement strstr
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last_solved:
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category: string
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leetcode_url: https://leetcode.com/problems/implement-strstr
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status: Attempted
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---
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Problem
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-------
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```
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Implement strStr().
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Return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.
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Example 1:
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Input: haystack = "hello", needle = "ll"
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Output: 2
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Example 2:
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Input: haystack = "aaaaa", needle = "bba"
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Output: -1
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```
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Solution
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----------
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{% highlight python %}
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def strStr(self, haystack: str, needle: str) -> int:
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# "hello" "ll"
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if not needle: return 0
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for i in range(len(haystack)):
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if haystack[i]==needle[0]:
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substr = haystack[i:i+len(needle)]
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if substr==needle:
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return i
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return -1
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{% endhighlight %}
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![image1]() |