bzoj 1030 分类： bzoj templates 2015-08-06 17:34 10人阅读 评论(0) 收藏

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AC自动机模板

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#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <ctime>
#include <string>
#include <map>
#include <vector>
#include <stack>
#include <queue>
#include <utility>
#include <iostream>
#include <algorithm>

template<class Num>void read(Num &x)
{
    char c; int flag = 1;
    while((c = getchar()) < '0' || c > '9')
        if(c == '-') flag *= -1;
    x = c - '0';
    while((c = getchar()) >= '0' && c <= '9')
        x = (x<<3) + (x<<1) + (c-'0');
    x *= flag;
    return;
}
template<class Num>void write(Num x)
{
    if(x < 0) putchar('-'), x = -x;
    static char s[20];int sl = 0;
    while(x) s[sl++] = x%10 + '0',x /= 10;
    if(!sl) {putchar('0');return;}
    while(sl) putchar(s[--sl]);
}

const int maxn = 105, maxl = 105, size = 26, Mod = 10007;

struct TrieNode
{
    TrieNode *p[size], *fail;
    bool end;
    int dp[maxl];

}T[maxn*maxl], *root;
int n, m, tot;

char c[maxl];

TrieNode *NewNode()
{
    return T + (++tot);
}

void insert(char *t,TrieNode *now)
{
    if(!(*t)) 
    {
        now->end = true;
        return;
    }

    TrieNode *&next = now->p[(*t)-'A'];

    if(!next) next = NewNode();
    insert(t + 1, next);
}

void init()
{
    read(n), read(m);

    root = NewNode(); 

    for(int i = 1; i <= n; i++)
    {
        scanf("%s",c);
        insert(c, root);
    }
}


void build()
{
    std::queue<TrieNode*>line;

    root->fail = root;

    for(int i = 0; i < size; i++)
        if(root->p[i])
        {
            root->p[i]->fail = root;
            line.push(root->p[i]);
        }
        else
            root->p[i] = root;  

    while(!line.empty())
    {
        TrieNode *x = line.front();
        line.pop();

        for(int i = 0; i < size; i++)
        {
            if(x->p[i])
            {
                x->p[i]->fail = x->fail->p[i];
                line.push(x->p[i]); 
            }
            else
                x->p[i] = x->fail->p[i];
        }

        if(x->fail->end) x->end = true;
    }
}

void update(int len)
{   
    for(int x = 1; x <= tot; x++) 
        for(int i = 0; i < size; i++)
            if(!T[x].p[i]->end)
            {
                T[x].p[i]->dp[len] += T[x].dp[len-1];
                T[x].p[i]->dp[len] %= Mod;
            }
}

long long getans()
{
    long long ans = 0, sum = 1;

    for(int i = 1; i <= tot; i++)
        ans += T[i].dp[m], ans %= Mod;
    for(int i = 1; i <= m; i++)
        sum *= size, sum %= Mod;

    ans = (sum - ans + Mod)%Mod;

    return ans; 
}

int main()
{
#ifndef ONLINE_JUDGE
    freopen("1030.in","r",stdin);
    freopen("1030.out","w",stdout);
#endif

    init(), build();

    root->dp[0] = 1;
    for(int i = 1; i <= m; i++)
        update(i);

    write(getans());

#ifndef ONLINE_JUDGE
    fclose(stdin);
    fclose(stdout);
#endif
    return 0;       
}

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