BZOJ 1212: [HNOI2004]L语言

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AC自动机水题

跑一遍就好了

#include<iostream>#include<cstdio>#include<cstring>#include<queue>using namespace std;struct node{int fail,len,ch[26];void clear(){fail=len=0;memset(ch,0,sizeof(ch));}}tr[205];int sz;void ins(char *s){int u=0,n=strlen(s);for(int i=0;i<n;i++){int c=s[i]-'a';if(!tr[u].ch[c]){tr[u].ch[c]=++sz;tr[sz].clear();}u=tr[u].ch[c];}tr[u].len=n;}void bfs(){queue<int>q;q.push(0);while(!q.empty()){int u=q.front();q.pop();for(int i=0;i<26;i++)if(tr[u].ch[i]){int v=tr[u].ch[i];if(u)tr[v].fail=tr[tr[u].fail].ch[i];q.push(v);}else tr[u].ch[i]=tr[tr[u].fail].ch[i];}}bool f[1000005];int dfs(char *s){int n=strlen(s+1);memset(f,0,sizeof(f));f[0]=1;int p=0;for(int i=1;i<=n;i++){int c=s[i]-'a';p=tr[p].ch[c];if(!p)break;for(int q=p;q;q=tr[q].fail)f[i]|=f[i-tr[q].len];}for(int i=n;i>=0;i--)if(f[i])return i;}char s[1000005];int main(){//freopen("a.in","r",stdin);int n,m;scanf("%d%d",&n,&m);tr[sz=0].clear();for(int i=1;i<=n;i++){scanf("%s",s);ins(s);}bfs();while(m--){scanf("%s",s+1);printf("%d\n",dfs(s));}return 0;}

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