BZOJ 4032 HEOI2015 shortest non-public sub-string suffix automation + sequence automation + BFS, bzojheoi2015

BZOJ 4032 HEOI2015 shortest non-public sub-string suffix automation + sequence automation + BFS, bzojheoi2015

Given strings A and B, find the shortest substring/subsequence S to satisfy the substring/subsequence S which is not B
This question is really TM toxic * 2
Similar to this question
Then the sub-string is a suffix. The sub-sequence of the automatic machine is naturally a sequential automatic machine =.
Each time an x node is updated, all subsequent nodes without x are connected to this node.
The parent of each node is the last occurrence of the letter.
Each letter records the last position that appears when updating the pointer along the parent pointer again.

#include <cstdio>#include <cstring>#include <iostream>#include <algorithm>#define M 4040using namespace std;char A[M],B[M];struct Suffix_Automaton{    struct Sam{        Sam *son[26],*parent;        int max_dpt;        Sam() {}         Sam(int _):max_dpt(_) {}    }mempool[M],*C;    Sam *root,*last;    Suffix_Automaton()    {        C=mempool;        last=root=new (C++)Sam(0);    }    void Extend(int x)    {        Sam *p=last;        Sam *np=new (C++)Sam(p->max_dpt+1);        for(;p&&!p->son[x];p=p->parent)            p->son[x]=np;        if(!p)            np->parent=root;        else        {            Sam *q=p->son[x];            if(p->max_dpt+1==q->max_dpt)                np->parent=q;            else            {                Sam *nq=new (C++)Sam(p->max_dpt+1);                memcpy(nq->son,q->son,sizeof nq->son);                nq->parent=q->parent;                q->parent=nq;np->parent=nq;                for(;p&&p->son[x]==q;p=p->parent)                    p->son[x]=nq;            }        }        last=np;    }}substr_A,substr_B;struct Sequence_Automaton{    struct Sqa{        Sqa *son[26],*parent;    }mempool[M],*C;    Sqa *root,*last[27];    Sequence_Automaton()    {        C=mempool;        last[26]=root=new (C++)Sqa;    }    void Extend(int x)    {        Sqa *p,*np=new (C++)Sqa;        int i;        for(i=0;i<=26;i++)            for(p=last[i];p&&!p->son[x];p=p->parent)                p->son[x]=np;        np->parent=last[x];        last[x]=np;    }}subseq_A,subseq_B;struct abcd{    int x,y,dpt;    abcd() {}    abcd(int _,int __,int ___):        x(_),y(__),dpt(___) {}}q[M];int v[M][M];int BFS1()//str-str{    int i,r=0,h=0;    q[++r]=abcd(0,0,0);    v[0][0]=true;    while(r!=h)    {        abcd sta=q[++h];        for(i=0;i<26;i++)        {            if(!substr_A.mempool[sta.x].son[i]) continue;            if(!substr_B.mempool[sta.y].son[i]) return sta.dpt+1;            int xx=substr_A.mempool[sta.x].son[i]-substr_A.root;            int yy=substr_B.mempool[sta.y].son[i]-substr_B.root;            if(v[xx][yy]==1) continue;            v[xx][yy]=1;            q[++r]=abcd(xx,yy,sta.dpt+1);        }    }    return -1;}int BFS2()//str-seq{    int i,r=0,h=0;    q[++r]=abcd(0,0,0);    v[0][0]=true;    while(r!=h)    {        abcd sta=q[++h];        for(i=0;i<26;i++)        {            if(!substr_A.mempool[sta.x].son[i]) continue;            if(!subseq_B.mempool[sta.y].son[i]) return sta.dpt+1;            int xx=substr_A.mempool[sta.x].son[i]-substr_A.root;            int yy=subseq_B.mempool[sta.y].son[i]-subseq_B.root;            if(v[xx][yy]==2) continue;            v[xx][yy]=2;            q[++r]=abcd(xx,yy,sta.dpt+1);        }    }    return -1;}int BFS3()//seq-str{    int i,r=0,h=0;    q[++r]=abcd(0,0,0);    v[0][0]=true;    while(r!=h)    {        abcd sta=q[++h];        for(i=0;i<26;i++)        {            if(!subseq_A.mempool[sta.x].son[i]) continue;            if(!substr_B.mempool[sta.y].son[i]) return sta.dpt+1;            int xx=subseq_A.mempool[sta.x].son[i]-subseq_A.root;            int yy=substr_B.mempool[sta.y].son[i]-substr_B.root;            if(v[xx][yy]==3) continue;            v[xx][yy]=3;            q[++r]=abcd(xx,yy,sta.dpt+1);        }    }    return -1;}int BFS4()//seq-seq{    int i,r=0,h=0;    q[++r]=abcd(0,0,0);    v[0][0]=true;    while(r!=h)    {        abcd sta=q[++h];        for(i=0;i<26;i++)        {            if(!subseq_A.mempool[sta.x].son[i]) continue;            if(!subseq_B.mempool[sta.y].son[i]) return sta.dpt+1;            int xx=subseq_A.mempool[sta.x].son[i]-subseq_A.root;            int yy=subseq_B.mempool[sta.y].son[i]-subseq_B.root;            if(v[xx][yy]==4) continue;            v[xx][yy]=4;            q[++r]=abcd(xx,yy,sta.dpt+1);        }    }    return -1;}int main(){    //freopen("sus.in","r",stdin);    //freopen("sus.out","w",stdout);    int i;    scanf("%s%s",A+1,B+1);    for(i=1;A[i];i++)    {        substr_A.Extend(A[i]-'a');        subseq_A.Extend(A[i]-'a');    }    for(i=1;B[i];i++)    {        substr_B.Extend(B[i]-'a');        subseq_B.Extend(B[i]-'a');    }    cout<<BFS1()<<endl;    cout<<BFS2()<<endl;    cout<<BFS3()<<endl;    cout<<BFS4()<<endl;    return 0;}