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#include<cstdio> 
#include<cstring>
#include<algorithm>
using namespace std;
#define N 500010
char st[N];
struct {
	int len, fail, p[26], dp;
}a[N];
int tot = 1;
int main() {
	int i, j; 
	a[0].dp = a[1].dp = 0;
	a[0].len = 0, a[1].len = -1;
	a[0].fail = 1;
	int la = 0, ls = 0;
	while(1) {
		i++;
		scanf("%c", &st[i]);
		if(st[i] < 'a' || st[i] > 'z') break;
		st[i] = (st[i] - 97 + ls) % 26 + 97;
		int x = la;
		while(st[i] != st[i - 1 - a[x].len]) x = a[x].fail;
		if(!a[x].p[st[i] - 'a']) a[x].p[st[i] - 'a'] = ++tot;
		la = a[x].p[st[i] - 'a'];
		a[la].len = a[x].len + 2;
		if(a[la].len == 1) x = 0;
		else {
			x = a[x].fail;
			while(st[i] != st[i - 1 - a[x].len]) x = a[x].fail;
			x = a[x].p[st[i] - 'a'];
		}
		a[la].dp = a[x].dp + 1;
		a[la].fail = x;
		ls = a[la].dp;
		printf("%d ", ls);
	}
	return 0;
}
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原文地址:https://www.cnblogs.com/LZA119/p/14623422.html