bzoj1030 [JSOI2007]文本生成器
AC自动机+DP
有点像GT考试，hh[i][j]表示第i为匹配到自动机上j号结点的方案数
1 #include<algorithm> 2 #include<iostream> 3 #include<cstdlib> 4 #include<cstring> 5 #include<cstdio> 6 #include<string> 7 #include<cmath> 8 #include<ctime> 9 #include<queue> 10 #include<stack> 11 #include<map> 12 #include<set> 13 #define rre(i,r,l) for(int i=(r);i>=(l);i--) 14 #define re(i,l,r) for(int i=(l);i<=(r);i++) 15 #define Clear(a,b) memset(a,b,sizeof(a)) 16 #define inout(x) printf("%d",(x)) 17 #define douin(x) scanf("%lf",&x) 18 #define strin(x) scanf("%s",(x)) 19 #define LLin(x) scanf("%lld",&x) 20 #define op operator 21 #define CSC main 22 typedef unsigned long long ULL; 23 typedef const int cint; 24 typedef long long LL; 25 using namespace std; 26 void inin(int &ret) 27 { 28 ret=0;int f=0;char ch=getchar(); 29 while(ch<'0'||ch>'9'){if(ch=='-')f=1;ch=getchar();} 30 while(ch>='0'&&ch<='9')ret*=10,ret+=ch-'0',ch=getchar(); 31 ret=f?-ret:ret; 32 } 33 int n,m,ch[6060][26],pre[6060],hh[111][6060],v[6060],ed=1,last[6060]; 34 char s[1010]; 35 void add(char *s,int x) 36 { 37 int temp=1,len=strlen(s); 38 re(i,0,len-1) 39 { 40 int c=s[i]-'A'; 41 if(!ch[temp][c])ch[temp][c]=++ed; 42 temp=ch[temp][c]; 43 } 44 v[temp]=x; 45 } 46 void getfail() 47 { 48 queue<int>h;int k; 49 h.push(1); 50 while(!h.empty()) 51 { 52 int x=h.front();h.pop(); 53 re(i,0,25) 54 { 55 if(!ch[x][i])continue; 56 int vv=ch[x][i]; 57 h.push(vv); 58 k=pre[x]; 59 while(!ch[k][i])k=pre[k]; 60 pre[vv]=ch[k][i]; 61 if(v[ch[k][i]])v[ch[x][i]]=v[ch[k][i]]; 62 last[vv]=v[pre[vv]]?pre[vv]:last[pre[vv]]; 63 } 64 } 65 } 66 cint mod=10007; 67 void dp(int x) 68 { 69 re(i,1,ed) 70 { 71 if(v[i]||!hh[x-1][i])continue; 72 re(j,0,25) 73 { 74 int k=i; 75 while(!ch[k][j])k=pre[k]; 76 (hh[x][ch[k][j]]+=hh[x-1][i])%=mod; 77 } 78 } 79 } 80 int main() 81 { 82 inin(n),inin(m); 83 re(i,0,25)ch[0][i]=1; 84 re(i,1,n) 85 { 86 strin(s); 87 add(s,i); 88 } 89 getfail(); 90 hh[0][1]=1; 91 re(i,1,m)dp(i); 92 int ans1=0,ans2=1; 93 re(i,1,m)ans2=ans2*26%mod; 94 re(i,1,ed)if(!v[i])(ans1+=hh[m][i])%=mod; 95 printf("%d",(ans2-ans1+mod)%mod); 96 return 0; 97 }
