HDU 4416 Good Article Good sentence（后缀自动机）

#include <cstdio>
#include <cstring>
#include <algorithm> 
using namespace std;
const int N=200005;
char s[N];
struct sam{
	  int p,q,np,nq,cnt,last,a[N][26],l[N],f[N];
	  sam(){cnt=0;last=++cnt;}
	  int val(int c){return l[c]-l[f[c]];} 
	  void init(){
	      cnt=0;last=++cnt;
	      memset(a,0,sizeof(a));
	      memset(l,0,sizeof(l));
	      memset(f,0,sizeof(f));
	      memset(b,0,sizeof(b));
	      memset(u,0,sizeof(u));
	  }
	  void extend(int c){
		    p=last;np=last=++cnt;l[np]=l[p]+1;
		    while(!a[p][c]&&p)a[p][c]=np,p=f[p];
		    if(!p)f[np]=1;
		    else{
			      q=a[p][c];
			      if(l[p]+1==l[q])f[np]=q;
			      else{
				        nq=++cnt;l[nq]=l[p]+1;
				        memcpy(a[nq],a[q],sizeof(a[q]));
				        f[nq]=f[q]; f[np]=f[q]=nq;
				        while(a[p][c]==q)a[p][c]=nq,p=f[p];
			      }
		    }
	  }int b[N],x[N],n;
	  void build(){
		    scanf("%s",s+1);
		    int len=strlen(s+1);n=len;
		    for(int i=1;i<=len;i++)extend(s[i]-‘a‘);
		    for(int i=1;i<=cnt;i++)b[l[i]]++;
		    for(int i=1;i<=len;i++)b[i]+=b[i-1];
		    for(int i=1;i<=cnt;i++)x[b[l[i]]--]=i;
	  }int u[N];
	  void doit(){
		    scanf("%s",s+1);
		    int p=1,len=strlen(s+1),tmp=0;
		    for(int i=1;i<=len;i++){
			      int c=s[i]-‘a‘;
			      if(a[p][c])p=a[p][c],tmp++,u[p]=max(u[p],tmp);
			      else{
				        while(p&&!a[p][c])p=f[p];
				        if(!p)p=1,tmp=0;
				        else tmp=l[p]+1,p=a[p][c],u[p]=max(u[p],tmp);
			      }
		    } 
		}
		void solve(){
		    long long ans=0;
		    for(int i=cnt;i;i--){
		        if(u[x[i]]){ 
		            u[f[x[i]]]=max(u[x[i]],u[f[x[i]]]);
		            if(u[x[i]]<l[x[i]])ans+=l[x[i]]-u[x[i]];
		        }else ans+=val(x[i]);
		    }printf("%I64d\n",ans);
		}
}sam;
int T,n,cas=1;
int main(){
    scanf("%d",&T);
    while(T--){
        scanf("%d",&n);
        sam.init();
        sam.build();
        for(int i=1;i<=n;i++)sam.doit();
        printf("Case %d: ",cas++);
        sam.solve();
    }return 0;
}