JZPGYZ - Sevenk Love Oimaster
Oimaster and sevenk love each other. But recently,sevenk heard that a girl named ChuYuXun was dating with oimaster. As a woman‘s nature, sevenk felt angry and began to check oimaster‘s online talk with ChuYuXun. Oimaster talked with ChuYuXun n times, and each online talk actually is a string. Sevenk asks q questions like this, "how many strings in oimaster‘s online talk contain this string as their substrings?"这篇文章讲述了一个sevenk如何用后缀自动机检查Oimaster的聊天记录......
题意：给出很多主串和很多询问串，求一个询问串在主串中出现次数
裸题啊.....除了我在http://www.cnblogs.com/candy99/p/sam.html中给出的方法
还有一种NlogN的做法，求出Parent树DFS序然后就是区间询问多少种不同的颜色，HH的项链.....注意一个点会有多种颜色
注意string别用错
#include <iostream>
#include <cstdio>
#include <algorithm>
#include <cstring>
#include <cmath>
#include <string>
using namespace std;
const int N=2e5+5,M=1e4+5;
typedef long long ll;
int n,Q;
string ss[M];
char s[N<<1];
struct node{
int ch[26],par,val;
int cou,cur;
}t[N];
int sz=1,root=1,last=1;
void extend(int c){
int p=last,np=++sz;
t[np].val=t[p].val+1;
for(;p&&!t[p].ch[c];p=t[p].par) t[p].ch[c]=np;
if(!p) t[np].par=root;
else{
int q=t[p].ch[c];
if(t[q].val==t[p].val+1) t[np].par=q;
else{
int nq=++sz;
t[nq]=t[q];t[nq].val=t[p].val+1;
t[q].par=t[np].par=nq;
for(;p&&t[p].ch[c]==q;p=t[p].par) t[p].ch[c]=nq;
}
}
last=np;
}
void solve(){
int u;
for(int i=1;i<=n;i++){
u=root; string &s=ss[i];
for(int j=0;j<s.size();j++){
u=t[u].ch[s[j]-‘a‘];
int p=u;
for(;p&&t[p].cur!=i;p=t[p].par) t[p].cou++,t[p].cur=i;
}
}
while(Q--){
scanf("%s",s);
int n=strlen(s),u=root,flag=0;
for(int i=0;i<n;i++){
int c=s[i]-‘a‘;
if(t[u].ch[c]) u=t[u].ch[c];
else{flag=1;break;}
}
if(flag) puts("0");
else printf("%d\n",t[u].cou);
}
}
int main(){
freopen("in","r",stdin);
scanf("%d%d",&n,&Q);
for(int i=1;i<=n;i++){
scanf("%s",s);
ss[i]=string(s);
last=root; int len=ss[i].size();
for(int j=0;j<len;j++) extend(s[j]-‘a‘);
}
solve();
}
时间： 2024-10-20 05:29:05