AC自动机+状态压缩+记忆化搜索+uva1076

You are the computer whiz for the secret organization known as the Sneaky Underground Smug Perpetrators of Evil Crimes and Thefts. The target for SUSPECT's latest evil crime is their greatest foe, the Indescribably Clever Policemen's Club, and everything is prepared. Everything, except for one small thing: the secret password for ICPC's main computer system.

The password is known to consist only of lowercase letters `a'-`z'. Furthermore, through various sneaky observations, you have been able to determine the length of the password, as well as a few (possibly overlapping) substrings of the password, though you do not know exactly where in the password they occur.

For instance, say that you know that the password is 10 characters long, and that you have observed the substrings ``hello" and ``world". Then the password must be either ``helloworld" or ``worldhello".

The question is whether this information is enough to reduce the number of possible passwords to a reasonable amount. To answer this, your task is to write a program that determines the number of possible passwords and, if there are at most 42 of them, prints them all.

Input 

The input file contains several test cases. Each test case begins with a line containing two integers N and M (1$ \le$N$ \le$25, 0$ \le$M$ \le$10), giving the length of the password and the number of known substrings respectively. This is followed by M lines, each containing a known substring. Each known substring consists of between 1 and 10 lowercase letters `a'-`z'.

The last test case is followed by a line containing two zeroes.

Output 

For each test case, print the case number (beginning with 1) followed by `Y suspects', where Y is the number of possible passwords for this case. If the number of passwords is at most 42, then output all possible passwords in alphabetical order, one per line.

The input will be such that the number of possible passwords at most 1015.

Sample Input 

10 2 
hello 
world 
10 0 
4 1 
icpc 
0 0

Sample Output 

Case 1: 2 suspects 
helloworld 
worldhello 
Case 2: 141167095653376 suspects 
Case 3: 1 suspects 
icpc


题意:告诉你m个子串,用他们构造出长度为n的串,有多少种构造方法,如果小于42中,则输出所有的串

思路:首先建立AC自动机,dp[i][j][k]表示长度为i,到达节点j,使用的单词集合为k的状态,然后根据自动机上的状态进行转移就行了

#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
#include
using namespace std;
typedef long long LL;
const int maxn=110;
const int SIGMA_SIZE=26;
int n,m,cas;
LL dp[30][105][1<<10];
char s[20];
vector str;
struct AC
{
    int ch[maxn][26],val[maxn];
    int fail[maxn],last[maxn];
    int sz;
    void clear(){memset(ch[0],0,sizeof(ch[0]));sz=1;}
    int idx(char x){return x-'a';}
    void insert(char * s,int id)
    {
        int n=strlen(s);
        int u=0;
        for(int i=0;i q;
        int u=0;
        fail[0]=0;
        for(int c=0;c=n)
        {
            str.push_back(st);
            return;
        }
        for(int c=0;c



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