https://www.luogu.com.cn/problem/P3805
板子题
比较模式的代码(书上整理):
#include<iostream>
#include<vector>
#include<algorithm>
#include<math.h>
#include<sstream>
#include<string>
#include<string.h>
#include<iomanip>
#include<map>
#include<queue>
#include<limits.h>
#include<climits>
using namespace std;
typedef long long ll;
const int N = 11000002;
int n, P[N *2];
char a[N], S[N *2];
void change()//功能:改成"$#x#x#^",比较值得注意的是:前后的末尾都是#再结束。
{
n = strlen(a);//不要用sizeof!
S[0] = '$';
int k = 2;
S[1] = '#';
for (int i = 0; i < n; i++)
{
S[k++] = a[i];
S[k++] = '#';
}
S[k++] = '^';
n = k;
}
void manacher()
{
int R=0, C;
for (int i = 0; i < n; i++)
{
if (i < R)P[i] = min(P[C * 2 - i], P[C] + C - i);//核心,比大小
else P[i] = 1;
while (S[i + P[i]] == S[i - P[i]])P[i]++;//左右开弓
if (i + P[i] > R)
{
R = i + P[i];
C = i;
}
}
}
int main()
{
scanf("%s", a);
change();
manacher();
int ans = 1;
for (int i = 0; i < n; i++)ans = max(ans, P[i]);
cout << ans -1 ;
return 0;
}
标签:int,manacher,++,ans,P3805,include,模板
From: https://www.cnblogs.com/zzzsacmblog/p/18064360