NOI2018 你的名字――SAM+线段树合并

匿名 (未验证) 提交于 2019-12-02 23:43:01

题目链接在这里洛谷/LOJ

有一个串\(S\),每次询问给你一个串\(T\),两个数\(L\)\(R\),问你\(T\)有多少个本质不同的子串不是\(S[L,R]\)的子串

SOLUTION

如果你做过生成魔咒CF1037H,就会做这道题了
有两个坑点:
1.线段树合并时必须每次都新建结点,因为两颗树都得保留
2.每次失配时必须先尝试减小已经匹配的长度,无法继续减少时再跳\(suflink\)
我的大常数代码

#include <algorithm> #include  <iostream> #include   <cstdlib> #include   <cstring> #include    <cstdio> #include    <random> #include    <string> #include    <vector> #include     <cmath> #include     <ctime> #include     <queue> #include       <map> #include       <set>  #define IINF 0x3f3f3f3f3f3f3f3fLL #define u64 unsigned long long #define pii pair<int, int> #define mii map<int, int> #define u32 unsigned int #define lbd lower_bound #define ubd upper_bound #define INF 0x3f3f3f3f #define vi vector<int> #define ll long long #define mp make_pair #define pb push_back #define is insert #define se second #define fi first #define ps push  #define $SHOW(x) cout << #x" = " << x << endl #define $DEBUG() printf("%d %s\n", __LINE__, __FUNCTION__)  using namespace std;  #define S 500000 #define Q 100000 #define T 1000000 #define mid ((l+r)>>1)  int q, n, m, L, R; char s[S+5], t[T+5]; int nid1 = 1, lst1 = 1, ch1[26][2*S+5], link1[2*S+5], len1[2*S+5], nodecnt, root[2*S+5], ch[2][200*S+5]; int nid, lst, nxt[26][2*T+5], link[2*T+5], len[2*T+5], rest[2*T+5], val[T+5]; ll ans = 0; int a[2*T+5], buc[2*T+5];  void add(int &o, int l, int r, int x) {     if (!o) o = ++nodecnt;     if (l == r) return ;     if (x <= mid) add(ch[0][o], l, mid, x);     else add(ch[1][o], mid+1, r, x); }  int merge(int x, int y, int l, int r) {     int u = ++nodecnt;     if (x * y == 0) u = x ? x : y;     else {         ch[0][u] = merge(ch[0][x], ch[0][y], l, mid);         ch[1][u] = merge(ch[1][x], ch[1][y], mid + 1, r);     }     return u; }  int query(int u, int l, int r, int L, int R) {     if (!u) return 0;     if (L <= l && r <= R) return 1;     int ret = 0;     if (L <= mid) ret |= query(ch[0][u], l, mid, L, R);     if (R > mid) ret |= query(ch[1][u], mid+1, r, L, R);     return ret; }  void build() {     for (int i = 1, c; i <= n; ++i) {         c = s[i] - 'a';         int cur = ++nid1;         len1[cur] = len1[lst1] + 1;         add(root[cur], 1, n, i);         while (lst1 && !ch1[c][lst1]) ch1[c][lst1] = cur, lst1 = link1[lst1];         if (!lst1) link1[cur] = 1;         else {             int p = lst1, q = ch1[c][lst1];             if (len1[q] == len1[p] + 1) link1[cur] = q;             else {                 int clone = ++nid1;                 len1[clone] = len1[p] + 1;                 for (int j = 0; j < 26; ++j) ch1[j][clone] = ch1[j][q];                 link1[clone] = link1[q], link1[cur] = link1[q] = clone;                 while (p && ch1[c][p] == q) ch1[c][p] = clone, p = link1[p];             }         }         lst1 = cur;     }     for (int i = 1; i <= nid1; ++i) buc[len1[i]]++;     for (int i = 1; i <= n; ++i) buc[i] += buc[i-1];     for (int i = 1; i <= nid1; ++i) a[buc[len1[i]]--] = i;     for (int i = nid1; i >= 2; --i) root[link1[a[i]]] = merge(root[link1[a[i]]], root[a[i]], 1, n); }  void extend(int c) {     int cur = ++nid;     len[cur] = len[lst] + 1;     for(int i = 0; i < 26; ++i) nxt[i][cur] = 0;     while (lst && !nxt[c][lst]) nxt[c][lst] = cur, lst = link[lst];     if (!lst) link[cur] = 1;     else {         int p = lst, q = nxt[c][lst];         if (len[q] == len[p] + 1) link[cur] = q;         else {             int clone = ++nid;             len[clone] = len[p] + 1;             for (int i = 0; i < 26; ++i) nxt[i][clone] = nxt[i][q];             link[clone] = link[q], link[q] = link[cur] = clone;             while (p && nxt[c][p] == q) nxt[c][p] = clone, p = link[p];         }     }     lst = cur; }  void calc() {     m = strlen(t+1);     lst = nid = 1;     int i, j, c;     for (i = 0; i < 26; ++i) nxt[i][1] = 0;     for (j = 1; j <= m; ++j) extend(t[j] - 'a');     for (i = 2; i <= nid; ++i) rest[i] = 0;     int u = 1, match = 0;     for (i = 1, c; i <= m; ++i) {         c = t[i] - 'a';         while (u && !query(root[ch1[c][u]], 1, n, L + match, R)) {             if(match > len1[link1[u]]) match--;             else u = link1[u], match = len1[u];         }         if (!u) u = 1, match = 0;         else u = ch1[c][u], match++;         val[i] = match;     }     u = 1;     for (i = 1; i <= m; ++i) u = nxt[t[i] - 'a'][u], rest[u] = val[i];     for (i = 0; i <= m; ++i) buc[i] = 0;     for (i = 1; i <= nid; ++i) buc[len[i]]++;     for (i = 1; i <= m; ++i) buc[i] += buc[i-1];     for (i = 1; i <= nid; ++i) a[buc[len[i]]--] = i;     for (i = nid; i >= 2; --i) rest[link[a[i]]] = max(rest[link[a[i]]], rest[a[i]]);     ll ans = 0;     for (i = 2; i <= nid; ++i) ans += max(0, min(len[i] - rest[i], len[i] - len[link[i]]));     printf("%lld\n", ans); }  int main() {     scanf("%s", s+1);     n = strlen(s+1);     build();     scanf("%d", &q);     for (int i = 1; i <= q; ++i) {         scanf("%s%d%d", t+1, &L, &R);         calc();     }     return 0; }
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