bzoj 3172 后缀数组|AC自动机

  后缀数组或者AC自动机都可以,模板题。

/**************************************************************
    Problem: 3172
    User: BLADEVIL
    Language: C++
    Result: Accepted
    Time:424 ms
    Memory:34260 kb
****************************************************************/
 
//By BLADEVIL
#include <cstdio>
#include <cstring>
#define maxn 2000010
#define maxm 300
 
using namespace std;
 
struct node{
    int cnt;
    node *fail,*child[30];
    node(){
        cnt=0; fail=NULL;
        memset(child,0,sizeof child);
    }
} *que[maxn],*root=new(node),*w[maxm];
 
int n;
 
int main(){
    scanf("%d",&n);
    for (int i=1;i<=n;i++){
        char c[maxn];
        scanf("%s",&c);
        int len=strlen(c);
        node *t=root;
        for (int j=0;j<len;j++){
            if (!t->child[c[j]-'a']) t->child[c[j]-'a']=new(node);
            t=t->child[c[j]-'a']; t->cnt++;
        }
        w[i]=t;
    }
    int h=0,t=1;
    root->fail=root; que[1]=root;
    while (h<t){
        node *u=que[++h];
        for (int i=0;i<26;i++) if (u->child[i]){
            que[++t]=u->child[i];
            node *v=u->fail;
            que[t]->fail=v->child[i]&&v->child[i]!=que[t]?v->child[i]:root;
        } else u->child[i]=u->fail->child[i];
    }
    for (int i=t;i;i--) que[i]->fail->cnt+=que[i]->cnt;
    for (int i=1;i<=n;i++) printf("%d\n",w[i]->cnt);
    return 0;
}
/**************************************************************
    Problem: 3172
    User: BLADEVIL
    Language: C++
    Result: Accepted
    Time:6660 ms
    Memory:107360 kb
****************************************************************/
//By BLADEVIL
#include <cstdio>
#include <cstring>
#include <algorithm>
#define maxn 1001000
#define maxm 300
  
using namespace std;
  
int n,len;
char s[maxn];
int sa[maxn],tsa[maxn],rk[maxn],trk[maxn],sum[maxn],h[maxn];
int w[maxn][21];
int adr[maxm],len_s[maxm];
  
inline void getsa(int j) {
    for (int i=1;i<=len;i++) sum[i]=0;
    for (int i=1;i<=len;i++) sum[rk[i+j]]++;
    for (int i=1;i<=len;i++) sum[i]+=sum[i-1];
    for (int i=len;i;i--) tsa[sum[rk[i+j]]--]=i;
      
    for (int i=1;i<=len;i++) sum[i]=0;
    for (int i=1;i<=len;i++) sum[rk[i]]++;
    for (int i=1;i<=len;i++) sum[i]+=sum[i-1];
    for (int i=len;i;i--) sa[sum[rk[tsa[i]]]--]=tsa[i];
}
  
inline int query(int l,int r) {
    int i,j;
    for (i=0,j=1;(j<<1)<=r-l+1;j<<=1,i++) ;
    return min(w[l][i],w[r-j+1][i]);
}
  
int main() {
    scanf("%d",&n); len=0;
    for (int i=1;i<=n;i++) {
        scanf("%s",s+len+1); 
        adr[i]=len+1;
        len=strlen(s+1);
        s[++len]='^';
        len_s[i]=len-adr[i];
    }
    //for (int i=1;i<=len;i++) printf("%c",s[i]); printf("\n");
    for (int i=1;i<=len;i++) sum[s[i]]++;
    for (int i=1;i<=255;i++) sum[i]+=sum[i-1];
    for (int i=len;i;i--) sa[sum[s[i]]--]=i;
    rk[sa[1]]=1;
    for (int i=2,p=1;i<=len;i++) {
        if (s[sa[i]]!=s[sa[i-1]]) p++;
        rk[sa[i]]=p;
    }
    for (int j=1;j<=len;j<<=1) {
        getsa(j);
        trk[sa[1]]=1;
        for (int i=2,p=1;i<=len;i++) {
            if (rk[sa[i]]!=rk[sa[i-1]]||rk[sa[i]+j]!=rk[sa[i-1]+j]) p++;
            trk[sa[i]]=p;
        }
        for (int i=1;i<=len;i++) rk[i]=trk[i];
    }
    for (int i=1,j=0;i<=len;i++) {
        if (rk[i]==1) continue;
        while (i+j<=len&&sa[rk[i]-1]+j<=len&&s[i+j]==s[sa[rk[i]-1]+j]) j++;
        h[rk[i]]=j;
        if (j) j--;
    }
    //for (int i=1;i<=len;i++) printf("%d ",sa[i]); printf("\n");
    //for (int i=1;i<=len;i++) printf("%d ",h[i]); printf("\n");
    memset(w,127,sizeof w);
    for (int i=1;i<=len;i++) w[i][0]=h[i];
    for (int j=1,k=1;j<21;j++,k<<=1)
        for (int i=1;i<=len;i++)
            if (i+k<=len) w[i][j]=min(w[i][j-1],w[i+k][j-1]);
    //for (int i=1;i<=len;i++) printf("%d ",w[i][2]); printf("\n");
    //printf("%d\n",query(5,8));
    //printf("%d\n",rk[6]);
    for (int i=1;i<=n;i++) {
        int l=1,r=rk[adr[i]],mid,left=rk[adr[i]],right=rk[adr[i]];
        while (l<=r) {
            mid=l+r>>1;
            if (query(mid+1,rk[adr[i]])>=len_s[i]) 
                left=mid,r=mid-1; else l=mid+1;
        }
        l=rk[adr[i]],r=len;
        while (l<=r) {
            mid=l+r>>1;
            if (query(rk[adr[i]]+1,mid)>=len_s[i])
                right=mid,l=mid+1; else r=mid-1;
        }
        printf("%d\n",right-left+1);
    }
    return 0;
}

 

posted on 2014-05-12 20:20  BLADEVIL  阅读(734)  评论(0编辑  收藏  举报