POJ 3691 DNA repair ( Trie图 && DP )

#include<queue>
#include<stdio.h>
#include<string.h>
using namespace std;

const int Max_Tot = 1111;
const int Letter  = 4;
const int INF = 0x3f3f3f3f;
int mp[128];

struct Aho{
    struct StateTable{
        int Next[Letter];
        int fail, flag;
    }Node[Max_Tot];
    int Size;
    queue<int> que;

    inline void init(){
        while(!que.empty()) que.pop();
        memset(Node[0].Next, 0, sizeof(Node[0].Next));
        Node[0].fail = Node[0].flag = 0;
        Size = 1;
    }

    inline void insert(char *s){
        int now = 0;
        for(int i=0; s[i]; i++){
            int idx = mp[s[i]];
            if(!Node[now].Next[idx]){
                memset(Node[Size].Next, 0, sizeof(Node[Size].Next));
                Node[Size].fail = Node[Size].flag = 0;
                Node[now].Next[idx] = Size++;
            }
            now = Node[now].Next[idx];
        }
        Node[now].flag = 1;
    }

    inline void BuildFail(){
        Node[0].fail = 0;
        for(int i=0; i<Letter; i++){
            if(Node[0].Next[i]){
                Node[Node[0].Next[i]].fail = 0;
                que.push(Node[0].Next[i]);
            }else Node[0].Next[i] = 0;///必定指向根节点
        }
        while(!que.empty()){
            int top = que.front(); que.pop();
            if(Node[Node[top].fail].flag) Node[top].flag = 1;
            for(int i=0; i<Letter; i++){
                int &v = Node[top].Next[i];
                if(v){
                    que.push(v);
                    Node[v].fail = Node[Node[top].fail].Next[i];
                }else v = Node[Node[top].fail].Next[i];
            }
        }
    }
}ac;
char S[1111];
int dp[1111][1111];

int main(void)
{
    mp[‘A‘] = 0,
    mp[‘T‘] = 1,
    mp[‘G‘] = 2,
    mp[‘C‘] = 3;
    int n, Case = 1;
    while(~scanf("%d", &n) && n){
        ac.init();
        for(int i=0; i<n; i++){
            scanf("%s", S);
            ac.insert(S);
        }
        ac.BuildFail();
        scanf("%s", S);
        int len = strlen(S);

        for(int i=0; i<=len; i++)
            for(int j=0; j<=ac.Size; j++)
                dp[i][j] = 2333;

        dp[0][0] = 0;

        for(int i=0; i<len; i++){
            for(int j=0; j<ac.Size; j++){
                if(dp[i][j] != 2333){
                    for(int k=0; k<4; k++){
                        int newi = i+1;
                        int newj = ac.Node[j].Next[k];
                        if(!ac.Node[newj].flag){
                            dp[newi][newj] = min(dp[newi][newj],
                                                 dp[i][j] + (k != mp[S[i]]) );
                        }
                    }
                }
            }
        }

        int ans = 2333;
        for(int i=0; i<ac.Size; i++)
            ans = min(ans, dp[len][i]);

        printf("Case %d: ", Case++);
        if(ans != 2333) printf("%d\n", ans);
        else puts("-1");
    }
    return 0;
}