CF235C Cyclical Quest

题意

给定一个长度为\(n\)的母串

\(q\)组询问

这个串可以旋转（就是把最后一位丢到最前面这样子）

问这个串以及其旋转的串在给定的串中出现了多少次

Sol

旋转就把它复制一遍接在后面

然后就在\(sam\)上匹配

跳\(parent\)树的父亲到最后一个长度大于等于询问串长

然后统计\(size\)

防止重复算，就标记一下这个点是否算过

# include <bits/stdc++.h>
# define RG register
# define IL inline
# define Fill(a, b) memset(a, b, sizeof(a))
using namespace std;
typedef long long ll;

IL int Input(){
    RG int x = 0, z = 1; RG char c = getchar();
    for(; c < '0' || c > '9'; c = getchar()) z = c == '-' ? -1 : 1;
    for(; c >= '0' && c <= '9'; c = getchar()) x = (x << 1) + (x << 3) + (c ^ 48);
    return x * z;
}

const int maxn(2e6 + 5);

int len[maxn], trans[26][maxn], fa[maxn], tot = 1, last = 1;
int n, q, id[maxn], t[maxn], size[maxn], vis[maxn];
char s[maxn];

IL void Extend(RG int c){
    RG int p = last, np = ++tot;
    len[last = np] = len[p] + 1, size[np] = 1;
    while(p && !trans[c][p]) trans[c][p] = np, p = fa[p];
    if(!p) fa[np] = 1;
    else{
        RG int q = trans[c][p];
        if(len[q] == len[p] + 1) fa[np] = q;
        else{
            RG int nq = ++tot;
            fa[nq] = fa[q], len[nq] = len[p] + 1;
            for(RG int i = 0; i < 26; ++i) trans[i][nq] = trans[i][q];
            fa[np] = fa[q] = nq;
            while(p && trans[c][p] == q) trans[c][p] = nq, p = fa[p];
        }
    }
}

int main(){
    scanf(" %s", s), n = strlen(s);
    for(RG int i = 0; i < n; ++i) Extend(s[i] - 'a');
    for(RG int i = 1; i <= tot; ++i) ++t[len[i]];
    for(RG int i = 1; i <= tot; ++i) t[i] += t[i - 1];
    for(RG int i = 1; i <= tot; ++i) id[t[len[i]]--] = i;
    for(RG int i = tot; i; --i) size[fa[id[i]]] += size[id[i]];
    q = Input();
    for(RG int i = 1, l, tl; i <= q; ++i){
        scanf(" %s", s + 1), l = strlen(s + 1);
        for(RG int j = 1; j < l; ++j) s[j + l] = s[j];
        RG ll ans = 0; tl = l + l;
        for(RG int j = 1, nw = 1, cnt = 0; j < tl; ++j){
            while(nw && !trans[s[j] - 'a'][nw]) nw = fa[nw], cnt = len[nw];
            if(!nw) nw = 1, cnt = 0;
            else ++cnt, nw = trans[s[j] - 'a'][nw];
            while(nw && len[fa[nw]] >= l) nw = fa[nw], cnt = len[nw];
            if(cnt >= l && vis[nw] != i) ans += size[nw], vis[nw] = i;
        }
        printf("%lld\n", ans);
    }
    return 0;
}