思路 这里我们要注意以下几点: 字符串哈希自然溢出(\(\pmod 2^64\))会被卡,会\(WA~5\)个点 注意有模数的时候不要用\(unsigned\ long \ long\)类型 代码 #include <iostream> using namespace std; typedef long long LL; const int N = 2000010,BASE = 131,MOD = 998244353; int n; char s[N]; LL p[N],h1[N],h2[N]…

回文字符串:即字符串从前往后读和从后往前读字符顺序是一致的. 如:字符串abccba,从前往后读是a-b-c-c-b-a:从后往前读也是a-b-c-c-b-a 方法一 function palindRome(str){ var len = str.length; var str1 = ""; for(var i=len-1; i>=0;i--){ str1+=str[i]; } console.log(str1 == str) } palindRome("abcba&q…

Description A palindrome is a string of symbols that is equal to itself when reversed. Given an input string, not necessarily a palindrome, compute the number of swaps necessary to transform the string into a palindrome. By swap we mean reversing the…

\[s=abcbacbcb\\ \begin{split} p \quad& fa \quad& Substrings \quad& Right \\ 1 \quad& - \quad& (Null) \quad& \{1,2,3,4,5,6,7,8,9\} \\ 2 \quad& 1 \quad& a \quad& \{1,5\} \\ 7 \quad& 2 \quad& ba..abcba \quad& \…

AtCoder Beginner Conest 284 解题报告 \(\text{By DaiRuiChen007}\) \(\text{Contest Link}\) A. Sequence of Strings 模拟,时间复杂度 \(\Theta(n)\) #include<bits/stdc++.h> using namespace std; signed main() { int n; cin>>n; vector <string> v(n); for(int…