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Rescue the Rabbit HOJ4507

2013年02月12日 ⁄ 综合 ⁄ 共 2559字 ⁄ 字号 评论关闭

AC自动机+DP


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

using std::priority_queue;
using std::vector;
using std::swap;
using std::stack;
using std::sort;
using std::max;
using std::min;
using std::pair;
using std::map;
using std::string;
using std::cin;
using std::cout;
using std::set;
using std::queue;
using std::string;
using std::istringstream;
using std::make_pair;
using std::getline;
using std::greater;
using std::endl;
using std::multimap;
using std::deque;

typedef long long LL;
typedef unsigned long long ULL;
typedef pair<int, int> PAIR;
typedef multimap<int, int> MMAP;

const int MAXN(1010);
const int SIGMA_SIZE(4);
const int MAXM(110);
const int MAXE(300010);
const int MAXH(18);
const int INFI((INT_MAX-1) >> 1);
const int MOD(2520);
const ULL LIM(1000000000000000ull);

map<char, int> mp;

struct AC
{
    int ch[MAXN][SIGMA_SIZE], f[MAXN];
    int val[MAXN];
    int size;
    inline int idx(char temp)
    {
        return mp[temp];
    }
    void init()
    {
        memset(ch[0], 0, sizeof(ch[0]));
        val[0] = 0;
        size = 1;
    }

    void insert(char *S, int tv)
    {
        int u = 0, id;
        for(; *S; ++S)
        {
            id = idx(*S);
            if(!ch[u][id])
            {
                memset(ch[size], 0, sizeof(ch[size]));
                val[size] = 0;
                ch[u][id] = size++;
            }
            u = ch[u][id];
        }
        val[u] |= (1 << tv);
    }

    int que[MAXN];
    int front, back;
    void construct()
    {
        int cur, u;
        front = back = 0;
        for(int i = 0; i < SIGMA_SIZE; ++i)
            if(ch[0][i])
            {
                u = ch[0][i];
                f[u] = 0;
                que[back++] = u;
            }
        while(front < back)
        {
            cur = que[front++];
            for(int i = 0; i < SIGMA_SIZE; ++i)
            {
                u = ch[cur][i];
                if(u)
                {
                    f[u] = ch[f[cur]][i];
                    val[u] |= val[f[u]];
                    que[back++] = u;
                }
                else
                    ch[cur][i] = ch[f[cur]][i];
            }
        }
    }
};

AC ac;

bool vis[2][1010][1 << 10];
int scoer[15];

int solve(int len, int n)
{
    int limit = (1 << n)-1;
    int cur = 0, last = 1;
    memset(vis[last], 0, sizeof(vis[last]));
    vis[last][0][0] = true;
    for(int i = 1; i <= len; ++i)
    {
        memset(vis[cur], 0, sizeof(vis[cur]));
        for(int j = 0; j < ac.size; ++j)
            for(int k = 0; k <= limit; ++k)
                if(vis[last][j][k])
                {
                    int u;
                    for(int k2 = 0; k2 < SIGMA_SIZE; ++k2)
                    {
                        u = ac.ch[j][k2];
                        vis[cur][u][k|ac.val[u]] = true;
                    }
                }
        cur ^= 1;
        last ^= 1;
    }
    int ans = -1;
    for(int i = 0; i <= limit; ++i)
    {
        bool flag = false;
        for(int j = 0; j < ac.size; ++j)
            if(vis[last][j][i])
            {
                flag = true;
                break;
            }
        if(flag)
        {
            int tans = 0;
            for(int j = 0; j < n; ++j)
                if(i&(1 << j))
                    tans += scoer[j];
            ans = max(ans, tans);
        }
    }
    return ans;
}

char str[110];

int main()
{
    mp.insert(make_pair('A', 0));
    mp.insert(make_pair('C', 1));
    mp.insert(make_pair('G', 2));
    mp.insert(make_pair('T', 3));
    int n, len;
    while(~scanf("%d%d", &n, &len))
    {
        ac.init();
        for(int i = 0; i < n; ++i)
        {
            scanf("%s%d", str, scoer+i);
            ac.insert(str, i);
        }
        ac.construct();
        int ans = solve(len, n);
        if(ans < 0)
            printf("No Rabbit after 2012!\n");
        else
            printf("%d\n", ans);
    }
    return 0;
}

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