hihocoder 1445 : 后缀自动机二·重复旋律5（后缀自动机）

来源：互联网发布：深圳压寨网络是培训么编辑：程序博客网时间：2024/05/17 07:52

给入门新手的模板题，套kuangbin大佬的模板。
当前节点的minlen就等于当前节点的fa节点的maxlen+1。

#include <bits/stdc++.h>using namespace std;const int CHAR = 26;const int MAXN = 1100010;long long res = 0;struct SAM_Node{    SAM_Node *fa,*next[CHAR];    int len;    int id,pos;    SAM_Node() {}    SAM_Node(int _len)    {        fa = 0;        len = _len;        memset(next,0,sizeof(next));    }};SAM_Node SAM_node[MAXN*2], *SAM_root, *SAM_last;int SAM_size;SAM_Node *newSAM_Node(int len){    SAM_node[SAM_size] = SAM_Node(len);    SAM_node[SAM_size].id = SAM_size;    return &SAM_node[SAM_size++];}SAM_Node *newSAM_Node(SAM_Node *p){    SAM_node[SAM_size] = *p;    SAM_node[SAM_size].id = SAM_size;    return &SAM_node[SAM_size++];}void SAM_init(){    SAM_size = 0;    SAM_root = SAM_last = newSAM_Node(0);    SAM_node[0].pos = 0;}void SAM_add(int x,int len){    SAM_Node *p = SAM_last, *np = newSAM_Node(p->len+1);    np->pos = len;    SAM_last = np;    for(; p && !p->next[x]; p = p->fa)        p->next[x] = np;    if(!p)    {        np->fa = SAM_root;        res += (np->len-np->fa->len);        return;    }    SAM_Node *q = p->next[x];    if(q->len == p->len + 1)    {        np->fa = q;        res += (np->len-np->fa->len);        return;    }    SAM_Node *nq = newSAM_Node(q);    nq->len = p->len + 1;    q->fa = nq;    np->fa = nq;    for(; p && p->next[x] == q; p = p->fa)        p->next[x] = nq;    res += (np->len-np->fa->len);}void SAM_build(char *s){    SAM_init();    int len = strlen(s);    for(int i = 0; i < len; i++)        SAM_add(s[i] - 'a',i+1);}char str[MAXN];int main(){    scanf("%s",str);    SAM_build(str);    printf("%lld\n",res);    return 0;}

阅读全文

0 0