UVA 11996 Jewel Magic —— splay、序列的分裂与合并、LCP的哈希算法

 #include <cstdio>
 #include <cstdlib>
 #include <iostream>
 #include <algorithm>
 #include <vector>

 using namespace std;

 typedef unsigned long long ull;
 const int x = ;
 const int maxn = 4e5 + ;

 ull xp[maxn];
 int n, m;
 struct Node {
     Node* ch[];
     int r, v, s;
     int val;
     ull Hush[];
     int flip;
     Node(int v1, int v2): v(v1), val(v2) {
         r = rand();
         s = ;
         ch[] = ch[] = NULL;
         flip = ;
         Hush[] = Hush[] = val;
     }
     bool cmp(const int &x) const {
         if(x == v) return -;
         return x < v ?  : ;
     }
     void maintain() {
         s = ;
         Hush[] = Hush[] = val;
         if(ch[] != NULL) s += ch[]->s, Hush[] = ch[]->Hush[ch[]->flip] + val*xp[ch[]->s];
         if(ch[] != NULL) Hush[] += (ch[]->Hush[ch[]->flip])*xp[s], s += ch[]->s;
         int s2 = ;
         if(ch[] != NULL) s2 += ch[]->s, Hush[] = ch[]->Hush[(ch[]->flip)^] + val*xp[ch[]->s];
         if(ch[] != NULL) Hush[] += (ch[]->Hush[(ch[]->flip)^])*xp[s2];
     }
     void pushdown() {
         if(flip) {
             flip = ;
             swap(ch[], ch[]);
             if(ch[] != NULL) ch[]->flip = !ch[]->flip;
             if(ch[] != NULL) ch[]->flip = !ch[]->flip;
         }
     }
 };

 void rotate(Node* &o, int d) {
     Node* k = o->ch[d^]; o->ch[d^] = k->ch[d]; k->ch[d] = o;
     o->maintain(); k->maintain(); o = k;
 }

 void insert(Node* &o, int x, int val) {
     if(o == NULL) o = new Node(x, val);
     else {
         int d = o->cmp(x);
         insert(o->ch[d], x, val);
         if(o->ch[d]->r > o->r) rotate(o, d^);
     }
     o->maintain();
 }
 void splay(Node* &o, int k) {
     o->pushdown();
     int s = o->ch[] == NULL ?  : o->ch[]->s;
     int d = k <= s ?  : (k == s+? - : );
     if(d == ) k -= s+;
     if(d != -) {
         splay(o->ch[d], k);
         rotate(o, d^);
     }
 }

 Node * merge(Node* left, Node* right) {
     splay(left, left->s);
     left->ch[] = right;
     left->maintain();
     return left;
 }
 void split(Node* o, int k , Node* &left, Node* &right) {
     splay(o, k);
     left = o;
     right = o->ch[];
     o->ch[] = NULL;
     left->maintain();
 }

 void oper1(Node* &o, int p, int c) {
     Node* left, *right;
     Node* node = new Node(p+, c);
     split(o, p+, left, right);
     o = merge(merge(left, node), right);
 }
 void oper2(Node* &o, int p) {
     Node* left, *mid, *right;
     split(o, p, left, mid);
     split(mid, , mid, right);
     o = merge(left, right);
 }
 void oper3(Node* &o, int p1, int p2) {
     Node *left, *mid, *right;
     split(o, p1, left, mid);
     split(mid, p2-p1+, mid, right);
     mid->flip ^= ;
     o = merge(merge(left, mid), right);
 }
 ull Hush_val(Node* &o, int p, int L) {
     Node *left, *mid, *right;
     split(o, p, left, mid);
     split(mid, L, mid, right);
     ull ans =  mid->Hush[mid->flip];
     o = merge(merge(left, mid), right);
     return ans;
 }
 int oper4(Node* &o, int p1, int p2) {
     int L = , R = min(n-p1+, n-p2+);
     while(L < R) {
         int M = R - (R-L)/;
         int l1 = Hush_val(o, p1, M), l2 =  Hush_val(o, p2, M);
         if(l1 == l2) L = M;
         else R = M-;
     }
     return L;
 }
 char s[maxn];
 int main() {
     xp[] = ;
     for(int i = ; i < maxn; i++) xp[i] = xp[i-]*x;
     while(scanf("%d%d", &n, &m) == ) {
         scanf("%s", s);
         Node* root = new Node(, );
         for(int i = ; i < n; i++) {
             int c = s[i] - '';
             insert(root, i+, c);
         }
         for(int i = ; i < m; i++) {
             int id, p1, p2;
             scanf("%d", &id);
             if(id == ) {
                 scanf("%d%d", &p1, &p2);
                 oper1(root, p1, p2);
                 n++;
             }
             if(id == ) {
                 scanf("%d", &p1);
                 oper2(root, p1);
                 n--;
             }
             if(id == ) {
                 scanf("%d%d", &p1, &p2);
                 oper3(root, p1, p2);
             }
             if(id == ) {
                 scanf("%d%d", &p1, &p2);
                 int ans = oper4(root, p1, p2);
                 printf("%d\n", ans);
             }
         }
     }
     return ;
 }