#6198. 谢特 [后缀自动机,01trie合并,启发式合并]

没啥意思的后缀自动机系列.jpg
怎么开心怎么搞.jpg

// 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;
using ull = unsigned long long;

#define pii pair<int, int>
#define fir first
#define sec second

template <class T>

void cmax(T& x, const T& y) {
  if (x < y) x = y;
}

template <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

template <class T>

void sort(vector<T>& v) {
  sort(all(v));
}

template <class T>

void reverse(vector<T>& v) {
  reverse(all(v));
}

template <class T>

void unique(vector<T>& v) {
  sort(all(v)), v.erase(unique(all(v)), v.end());
}

void reverse(string& s) { reverse(s.begin(), s.end()); }

const int io_size = 1 << 23 | 233;
const int io_limit = 1 << 22;
struct io_in {
  char ch;
#ifndef __WIN64
  char getchar() {
    static char buf[io_size], *p1 = buf, *p2 = buf;

    return (p1 == p2) && (p2 = (p1 = buf) + fread(buf, 1, io_size, stdin), p1 == p2) ? EOF : *p1++;
  }
#endif
  io_in& operator>>(char& c) {
    for (c = getchar(); isspace(c); c = getchar())
      ;

    return *this;
  }
  io_in& operator>>(string& s) {
    for (s.clear(); isspace(ch = getchar());)
      ;

    if (!~ch) return *this;

    for (s = ch; !isspace(ch = getchar()) && ~ch; s += ch)
      ;

    return *this;
  }

  io_in& operator>>(char* str) {
    char* cur = str;
    while (*cur) *cur++ = 0;

    for (cur = str; isspace(ch = getchar());)
      ;
    if (!~ch) return *this;

    for (*cur = ch; !isspace(ch = getchar()) && ~ch; *++cur = ch)
      ;

    return *++cur = 0, *this;
  }

  template <class T>

  void read(T& x) {
    bool f = 0;
    while ((ch = getchar()) < 48 && ~ch) f ^= (ch == 45);

    x = ~ch ? (ch ^ 48) : 0;
    while ((ch = getchar()) > 47) x = x * 10 + (ch ^ 48);
    x = f ? -x : x;
  }

  io_in& operator>>(int& x) { return read(x), *this; }

  io_in& operator>>(ll& x) { return read(x), *this; }

  io_in& operator>>(uint& x) { return read(x), *this; }

  io_in& operator>>(ull& x) { return read(x), *this; }

  io_in& operator>>(db& x) {
    read(x);
    bool f = x < 0;
    x = f ? -x : x;
    if (ch ^ '.') return *this;

    double d = 0.1;
    while ((ch = getchar()) > 47) x += d * (ch ^ 48), d *= .1;
    return x = f ? -x : x, *this;
  }
} in;

struct io_out {
  char buf[io_size], *s = buf;
  int pw[233], st[233];

  io_out() {
    set(7);
    rep(i, pw[0] = 1, 9) pw[i] = pw[i - 1] * 10;
  }

  ~io_out() { flush(); }

  void io_chk() {
    if (s - buf > io_limit) flush();
  }

  void flush() { fwrite(buf, 1, s - buf, stdout), fflush(stdout), s = buf; }

  io_out& operator<<(char c) { return *s++ = c, *this; }

  io_out& operator<<(string str) {
    for (char c : str) *s++ = c;
    return io_chk(), *this;
  }

  io_out& operator<<(char* str) {
    char* cur = str;
    while (*cur) *s++ = *cur++;
    return io_chk(), *this;
  }

  template <class T>

  void write(T x) {
    if (x < 0) *s++ = '-', x = -x;

    do {
      st[++st[0]] = x % 10, x /= 10;
    } while (x);

    while (st[0]) *s++ = st[st[0]--] ^ 48;
  }

  io_out& operator<<(int x) { return write(x), io_chk(), *this; }

  io_out& operator<<(ll x) { return write(x), io_chk(), *this; }

  io_out& operator<<(uint x) { return write(x), io_chk(), *this; }

  io_out& operator<<(ull x) { return write(x), io_chk(), *this; }

  int len, lft, rig;

  void set(int _length) { len = _length; }

  io_out& operator<<(db x) {
    bool f = x < 0;
    x = f ? -x : x, lft = x, rig = 1. * (x - lft) * pw[len];
    return write(f ? -lft : lft), *s++ = '.', write(rig), io_chk(), *this;
  }
} out;
#define int long long

template <int sz, int mod>

struct math_t {
  math_t() {
    fac.resize(sz + 1), ifac.resize(sz + 1);
    rep(i, fac[0] = 1, sz) fac[i] = fac[i - 1] * i % mod;

    ifac[sz] = inv(fac[sz]);
    Rep(i, sz - 1, 0) ifac[i] = ifac[i + 1] * (i + 1) % mod;
  }

  vector<int> fac, ifac;

  int qpow(int x, int y) {
    int ans = 1;
    for (; y; y >>= 1, x = x * x % mod)
      if (y & 1) ans = ans * x % mod;
    return ans;
  }

  int inv(int x) { return qpow(x, mod - 2); }

  int C(int n, int m) {
    if (n < 0 || m < 0 || n < m) return 0;
    return fac[n] * ifac[m] % mod * ifac[n - m] % mod;
  }
};

int gcd(int x, int y) { return !y ? x : gcd(y, x % y); }
int lcm(int x, int y) { return x * y / gcd(x, y); }

int n;
const int maxn = 2e5 + 52;
char str[maxn];
int w[maxn];
set<int> s[maxn];
vector<int> g[maxn];

int rt[maxn];
struct trie {
  int ch[maxn << 7][2], cnt;
  trie() { cnt = 0; }
  
  void ins(int &p, int v) {
    if (!p) p = ++cnt;
    int np = p;
    for (int i = 20; ~i; i--) {
      int c = (v >> i) & 1;
      if (!ch[np][c]) ch[np][c] = ++cnt;
      np = ch[np][c];
    }
  }

  int merge(int x, int y) {
    if (!x || !y) return x | y;
    ch[x][0] = merge(ch[x][0], ch[y][0]);
    ch[x][1] = merge(ch[x][1], ch[y][1]);
    return x;
  }

  int qry(int p, int v) {
    if (!p) return 0;
    int res = 0;
    for (int i = 20; ~i; i--) {
      int c = (v >> i) & 1;
      if (ch[p][c ^ 1]) {
        p = ch[p][c ^ 1];
        res |= 1 << i;
      } else {
        p = ch[p][c];
      }
    }
    return res;
  }
} tr;

struct suffixautomaton {
  int ch[maxn][26], fa[maxn], len[maxn], cnt, las;

  suffixautomaton() { cnt = las = 1; }

  void ins(int c, int v, int id) {
    int p = las, np = las = ++cnt;
    tr.ins(rt[np], v), len[np] = len[p] + 1, s[np].insert(id);
    for (; p && !ch[p][c]; p = fa[p]) ch[p][c] = np;
    if (!p) {
      fa[np] = 1;
    } else {
      int q = ch[p][c];
      if (len[q] == len[p] + 1) {
        fa[np] = q;
      } else {
        int nq = ++cnt;
        fa[nq] = fa[q], fa[q] = fa[np] = nq, len[nq] = len[p] + 1;
        memcpy(ch[nq], ch[q], sizeof(ch[q]));
        for (; p && ch[p][c] == q; p = fa[p]) ch[p][c] = nq;
      }
    }
  }

  void build() {
    for (int i = 2; i <= cnt; i++) g[fa[i]].pb(i);
  }
} sam;

int ans = 0;

void merge(int u, int v, int len) {
  if (sz(s[u]) < sz(s[v])) { swap(s[u], s[v]), swap(rt[u], rt[v]); }
  for (int x : s[v]) { cmax(ans, len + tr.qry(rt[u], w[x])), s[u].insert(x); }
  rt[u] = tr.merge(rt[u], rt[v]), s[v].clear();
}

void dfs(int u) { for (int v : g[u]) { dfs(v); merge(u, v, sam.len[u]); } }

signed main() {
  // code begin.
  in >> n, in >> str;
  for (int i = 0; i < n; i++) in >> w[i];
  reverse(str, str + n), reverse(w, w + n);
  for (int i = 0; i < n; i++) { sam.ins(str[i] - 'a', w[i], i); }
  sam.build(), dfs(1), out << ans << '\n';
  return 0;
  // code end.
}
posted @ 2020-04-14 21:06  _Isaunoya  阅读(118)  评论(0编辑  收藏  举报