POJ 1625 Censored! AC自动机+DP+大数

//#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<iostream>
#include<sstream>
#include<cmath>
#include<climits>
#include<string>
#include<map>
#include<queue>
#include<vector>
#include<stack>
#include<set>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> pii;
#define pb(a) push_back(a)
#define INF 0x1f1f1f1f
#define lson idx<<1,l,mid
#define rson idx<<1|1,mid+1,r
#define PI  3.1415926535898
template<class T> T min(const T& a,const T& b,const T& c) {
    return min(min(a,b),min(a,c));
}
template<class T> T max(const T& a,const T& b,const T& c) {
    return max(max(a,b),max(a,c));
}
void debug() {
#ifdef ONLINE_JUDGE
#else

    freopen("d:\in.txt","r",stdin);
   // freopen("d:\out1.txt","w",stdout);
#endif
}
int getch() {
    int ch;
    while((ch=getchar())!=EOF) {
        if(ch!=' '&&ch!='
')return ch;
    }
    return EOF;
}

struct BIG
{
    int bit[15];
    int len;
    BIG(){len=1;bit[0]=0;}
    BIG(int x){bit[0]=x;len=1;}
    BIG one()
    {
        BIG res;
        res.bit[0]=1;
        return res;
    }
    BIG operator += (const BIG &ans)
    {
        int nlen=max(len,ans.len);
        int next=0;
        for(int i=0;i<nlen;i++)
        {
            int x=(i<len?bit[i]:0)+(i<ans.len?ans.bit[i]:0)+next;
            next=x/1000000000;
            bit[i]=x%1000000000;
        }
        len = nlen;
        if(next)
            bit[len++]=next;
        return *this;
    }

    void output()
    {
        printf("%d",bit[len-1]);
        for(int i=len-2;i>=0;i--)
            printf("%09d",bit[i]);
       // printf("
");
    }
};
const int MAX_NODE=222;
const int SIGMA_SIZE = 50;

int ch[MAX_NODE][SIGMA_SIZE];
int fail[MAX_NODE];
int val[MAX_NODE];
int sz;

int n,m,p;

BIG dp[MAX_NODE][55];
int vis[MAX_NODE][55];
int id[256];

void init(int n)
{
    memset(id,-1,sizeof(id));
    char buf[55];
    scanf("%s",buf);
    for(int i=0;i<n;i++)
        id[buf[i]]=i;
    sz=1;
    memset(ch[0],0,sizeof(ch[0]));
    val[0]=0;

}

void insert(const char *s)
{
    int u=0;
    for(int i=0;s[i]!='';i++)
    {
        int v=id[s[i]];
        if(!ch[u][v])
        {
            memset(ch[sz],0,sizeof(ch[sz]));
            val[sz]=0;
            ch[u][v]=sz++;
        }
        u=ch[u][v];
    }
    val[u]=1;
}

void construct()
{
    fail[0]=0;
    queue<int> q;

    for(int c=0;c<SIGMA_SIZE;c++)
    {
        int u=ch[0][c];
        if(u){fail[u]=0;q.push(u);}
    }

    while(!q.empty())
    {
        int r=q.front();q.pop();

        for(int c=0;c<SIGMA_SIZE;c++)
        {
            int u=ch[r][c];
            if(!u)
            {
                ch[r][c]=ch[fail[r]][c];
                continue;
            }
            q.push(u);
            int v=fail[r];
            while(v&&!ch[v][c])v=fail[v];
            fail[u]=ch[v][c];
            val[u]|=val[fail[u]];
        }
    }
}

BIG f(int u,int k)
{
    if(!k)return BIG(1);
    if(vis[u][k])return dp[u][k];
    vis[u][k]=1;
    BIG x;
    for(int c=0;c<n;c++)
    {
        if(!val[ch[u][c]])
        {
            BIG xx=f(ch[u][c],k-1);
          //  x.output();
          //  xx.output();
            x+=xx;
          //  x.output();
            //x+=f(ch[u][c],k-1);
        }

    }
    return dp[u][k]=x;
}
int main()
{

    while(scanf("%d%d%d",&n,&m,&p)!=EOF)
    {
        init(n);
        for(int i=1;i<=p;i++)
        {
            char buf[55];
            scanf("%s",buf);
            insert(buf);
        }
        construct();

        memset(vis,0,sizeof(vis));
        BIG num=f(0,m);
        num.output();
        printf("
");
    }
    return 0;
}
View Code
原文地址:https://www.cnblogs.com/BMan/p/3415162.html