hdu 2457 DNA repair ac自动机+dp

来源：互联网发布：商机助理怎么传淘宝编辑：程序博客网时间：2024/06/02 13:29
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;}
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