P2414 [NOI2011]阿狸的打字机 [AC自动机，fail树，dfs序，树状数组]

板子，不说了/fad

// powered by c++11
// by Isaunoya
#include <bits/stdc++.h>
#define rep(i, x, y) for (register int i = (x); i <= (y); ++i)
#define Rep(i, x, y) for (register int i = (x); i >= (y); --i)
using namespace std;
using db = double;
using ll = long long;
using uint = unsigned int;
#define Tp template
using pii = pair<int, int>;
#define fir first
#define sec second
Tp<class T> void cmax(T& x, const T& y) {if (x < y) x = y;} Tp<class T> void cmin(T& x, const T& y) {if (x > y) x = y;}
#define all(v) v.begin(), v.end()
#define sz(v) ((int)v.size())
#define pb emplace_back
Tp<class T> void sort(vector<T>& v) { sort(all(v)); } Tp<class T> void reverse(vector<T>& v) { reverse(all(v)); }
Tp<class T> void unique(vector<T>& v) { sort(all(v)), v.erase(unique(all(v)), v.end()); }
const int SZ = 1 << 23 | 233;
struct FILEIN { char qwq[SZ], *S = qwq, *T = qwq, ch;
#ifdef __WIN64
#define GETC getchar
#else
  char GETC() { return (S == T) && (T = (S = qwq) + fread(qwq, 1, SZ, stdin), S == T) ? EOF : *S++; }
#endif
  FILEIN& operator>>(char& c) {while (isspace(c = GETC()));return *this;}
  FILEIN& operator>>(string& s) {while (isspace(ch = GETC())); s = ch;while (!isspace(ch = GETC())) s += ch;return *this;}
  Tp<class T> void read(T& x) { bool sign = 0;while ((ch = GETC()) < 48) sign ^= (ch == 45); x = (ch ^ 48);
    while ((ch = GETC()) > 47) x = (x << 1) + (x << 3) + (ch ^ 48); x = sign ? -x : x;
  }FILEIN& operator>>(int& x) { return read(x), *this; } FILEIN& operator>>(ll& x) { return read(x), *this; }
} in;
struct FILEOUT {const static int LIMIT = 1 << 22 ;char quq[SZ], ST[233];int sz, O;
  ~FILEOUT() { flush() ; }void flush() {fwrite(quq, 1, O, stdout); fflush(stdout);O = 0;}
  FILEOUT& operator<<(char c) {return quq[O++] = c, *this;}
  FILEOUT& operator<<(string str) {if (O > LIMIT) flush();for (char c : str) quq[O++] = c;return *this;}
  Tp<class T> void write(T x) {if (O > LIMIT) flush();if (x < 0) {quq[O++] = 45;x = -x;}
		do {ST[++sz] = x % 10 ^ 48;x /= 10;} while (x);while (sz) quq[O++] = ST[sz--];
  }FILEOUT& operator<<(int x) { return write(x), *this; } FILEOUT& operator<<(ll x) { return write(x), *this; }
} out;
#define int long long

int q ;
const int maxn = 1e5 + 51 ;
string s ;
int ed[maxn] , id = 0 ;
int cpy[maxn][26] ;
vector < int > g[maxn] ;
struct ACAM {
	int ch[maxn][26] , cnt = 1 , fa[maxn] , fail[maxn] ;
	void build() {
		int p = 1 ;
		for(char c : s) 
			if('a' <= c && c <= 'z') {
				if(! ch[p][c - 'a']) fa[ch[p][c - 'a'] = ++ cnt] = p ;
				p = ch[p][c - 'a'] ;
			}
			else if(c == 'P') ed[++ id] = p ;
			else if(c == 'B') p = fa[p] ;
		memcpy(cpy , ch , sizeof(ch)) ;
		queue <int> q ;
		for(int i = 0 ; i < 26 ; i ++)
			if(ch[1][i])
				fail[ch[1][i]] = 1 , q.push(ch[1][i]) ;
			else 
				ch[1][i] = 1 ;
		while(! q.empty()) {
			int u = q.front() ;
			q.pop() ;
			for(int i = 0 ; i < 26 ; i ++)
				if(ch[u][i]) 
					fail[ch[u][i]] = ch[fail[u]][i] , q.push(ch[u][i]) ;
				else 
					ch[u][i] = ch[fail[u]][i] ;
		}
		for(int i = 2 ; i <= cnt ; i ++)
			g[fail[i]].pb(i) ;
	}
} acam ;

int L[maxn] , R[maxn] , idx = 0 ;
void dfs(int u) {
	L[u] = ++ idx ;
	for(int v : g[u])
		dfs(v) ;
	R[u] = idx ;
}

int ans[maxn] ;
vector < pii > qr[maxn] ;

struct BIT {
	int c[maxn + 5] ;
	int low(int x) {
		return x & -x ;
	}
	void add(int x , int y) {
		for( ; x <= maxn ; x += low(x))
			c[x] += y ;
	}
	int qry(int x) {
		int ans = 0 ;
		for( ; x ; x ^= low(x))
			ans += c[x] ;
		return ans ;
	}
} bit ;

void solve(int u) {
	bit.add(L[u] , 1) ;
	for(auto x : qr[u])
		ans[x.second] = bit.qry(R[ed[x.first]]) - bit.qry(L[ed[x.first]] - 1) ;
	for(int i = 0 ; i < 26 ; i ++)
		if(cpy[u][i])
			solve(cpy[u][i]) ;
	bit.add(L[u] , -1) ;
}

signed main() {
  // code begin.
	in >> s ;
	in >> q ;
	acam.build() ;
	dfs(1) ;
	for(int i = 1 ; i <= q ; i ++) {
		int a , b ;
		in >> a >> b ;
		qr[ed[b]].pb(a , i) ;
	}
	solve(1) ;
	for(int i = 1 ; i <= q ; i ++)
		out << ans[i] << '
' ;
	return 0;
  // code end.
}