hdu 2457 DNA repair ac自动机+dp

链接：http://acm.hdu.edu.cn/showproblem.php?pid=2457

109ms

#pragma comment(linker, "/STACK:102400000,102400000")
#include <iostream>
#include <cstdio>
#include <cstring>
#include <algorithm>
#include<queue>
using namespace std;
typedef unsigned long long LL;
const int INF = 0x3f3f3f3f;
const int SN = 4;
const int MN = 1005;
int id['Z'];

class AAM{
public:
    int ch[MN][SN],tag[MN],fail[MN];
    int root,cnt;
    void init(){
        cnt = 0,root = cnt++;
        memset(ch[0],0,sizeof(ch[0]));
        memset(tag,0,sizeof(tag));
        memset(fail,0,sizeof(fail));
    }
    void insert(char *s){
        int p = root;
        while(*s){
                int  index = id[*s];
                if(tag[p]) return;//小小的优化
                if(!ch[p][index]){
                    ch[p][index] = cnt;
                    memset(ch[cnt],0,sizeof(ch[cnt]));
                    ++cnt;
                }
                p = ch[p][index];
                s++;
        }
        tag[p] = 1;
    }
    void getfail(){
            queue<int> Q;
            for(int i = 0; i < SN; ++i){//两个数组都有清零不用再赋0给他了
                 if(ch[0][i]){
                        Q.push(ch[0][i]);
                 }
            }
            while(!Q.empty()){
                int u = Q.front();Q.pop();
                if(tag[fail[u]]) tag[u] = 1;
                for(int i = 0;i < SN; ++i){
                    int &v = ch[u][i];
                    if(v){
                          fail[v] = ch[fail[u]][i];
                          Q.push(v);
                    }else v = ch[fail[u]][i];
                }
            }
    }
};
char s[1005];
int dp[MN][MN];
int n;
AAM T;
int main()
{
    int cas = 1;
    id['A'] = 0;id['T'] = 1;id['G'] = 2;id['C'] = 3;
    while(scanf("%d",&n),n){
            T.init();
            memset(dp,0x3f,sizeof(dp));
            for(int i = 0; i < n; ++i){
                scanf("%s",s);
                T.insert(s);
            }
            T.getfail();
            scanf("%s",s);
            dp[0][0] = 0;
            int len = strlen(s);
            for(int i = 1; i <= len; ++i)
                for(int j = 0; j < T.cnt; ++j)
                    for(int k = 0; k < 4; ++k){
                        int idx = T.ch[j][k];
                        if(T.tag[idx]) continue;
                        dp[i][idx] = min(dp[i][idx],dp[i - 1][j] + (k != id[s[i - 1]]) );
                    }
            int ans = INF;
            for(int i = 0; i < T.cnt; ++i)
                ans = min(ans,dp[len][i]);
            printf("Case %d: %d\n",cas++,ans == INF? -1:ans);
    }
    return 0;
}