add: 230303

This commit is contained in:
Eatswap 2023-03-03 19:09:47 +08:00
parent f76f1f9566
commit 755c0c2800
Signed by: Eatswap
GPG Key ID: BE661106A1F3FA0B
2 changed files with 34 additions and 1 deletions

33
cpp/2303/230303.cpp Normal file
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@ -0,0 +1,33 @@
#include <string>
#include <vector>
#include <iostream>
/**
* 28. Find the Index of the First Occurrence in a String
*
* Given two strings needle and haystack, return the index of the first occurrence of needle in haystack, or -1 if needle is not part of haystack.
*/
class Solution {
public:
static int strStr(const std::string& s, const std::string& t) {
const int m = s.length(), n = t.length();
std::vector<int> p(n);
for (int i = 1; i < n; ++i) {
int j = p[i - 1];
for (; j > 0 && t[i] != t[j]; j = p[j - 1]);
p[i] = j + (t[i] == t[j]);
}
for (int i = 0, j = 0; i < m; ++i) {
for (; j > 0 && s[i] != t[j]; j = p[j - 1]);
if (s[i] == t[j] && ++j >= n)
return i - j + 1;
}
return -1;
}
};
int main() {
std::cout << Solution::strStr("busasasasasapsadpp", "sasasasapsad");
return 0;
}

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@ -3,4 +3,4 @@ PROJECT(2303)
SET(CMAKE_CXX_STANDARD 23)
ADD_EXECUTABLE(2303 230302.cpp)
ADD_EXECUTABLE(2303 230303.cpp)