【ZOJ】3430 Detect the Virus

动态建树MLE。模仿别人的代码模板各种原因wa后，终于AC。

#include <iostream>
#include <cstdio>
#include <cstring>
#include <queue>
using namespace std;

#define MAXN  515*70
#define NXTN  256

bool visit[515];
char str[3005];
unsigned char buf[2050], src[3005];

typedef struct {
    int next[MAXN][NXTN], fail[MAXN], v[MAXN];
    int root, n;
    void init() {
        n = 0;
        root = newNode();
    }
    int newNode() {
        for (int i=0; i<NXTN; ++i)
            next[n][i] = -1;
        v[n] = 0;
        return n++;
    }
    void create(unsigned char s[], int len, int in) {
        int i = 0, cur = root, tmp;

        while (i < len) {
            if (next[cur][s[i]] == -1) {
                tmp = newNode();
                next[cur][s[i]] = tmp;
            }
            cur = next[cur][s[i]];
            ++i;
        }
        v[cur] = in;
    }
    void build() {
        int i, cur;
        queue<int> que;

        fail[root] = root;
        for (i=0; i<NXTN; ++i) {
            if (next[root][i] == -1) {
                next[root][i] = root;
            } else {
                fail[next[root][i]] = root;
                que.push(next[root][i]);
            }
        }

        while (!que.empty()) {
            cur = que.front();
            que.pop();
            for (i=0; i<NXTN; ++i) {
                if (next[cur][i] == -1) {
                    next[cur][i] = next[fail[cur]][i];
                } else {
                    fail[next[cur][i]] = next[fail[cur]][i];
                    que.push(next[cur][i]);
                }
            }
        }
    }
    void query(unsigned char s[], int len) {
        int i = 0, cur = root, tmp;

        memset(visit, false, sizeof(visit));
        while (i < len) {
            cur = next[cur][s[i]];
            tmp = cur;
            while (tmp != root) {
                visit[v[tmp]] = true;
                tmp = fail[tmp];
            }
            ++i;
        }
    }
} AC;

void output(int n) {
    int ans = 0;
    for (int i=1; i<=n; ++i)
        if (visit[i])
            ++ans;
    printf("%d
", ans);
}

unsigned char getVal(char c) {
    if (c>='A' && c<='Z')
        return c - 'A';
    if (c>='a' && c<='z')
        return c - 'a' + 26;
    if (c>='0' && c<='9')
        return c - '0' + 52;
    if (c == '+') return 62;
    return 63;
}

int decode(unsigned char src[], int len) {
    int i, k = 0;

    for (i=0; i<len; i+=4) {
        buf[k++] = (src[i]<<2)+(src[i+1]>>4);
        if (i+2 < len)
            buf[k++] = (src[i+1]<<4) + (src[i+2]>>2);
        if (i+3 < len)
            buf[k++] = (src[i+2]<<6) + (src[i+3]);
    }
    return k;
}

AC ac;

int main() {
    int i, j, l, n, m;


    while (scanf("%d", &n) != EOF) {
        ac.init();
        for (i=1; i<=n; ++i) {
            scanf("%s", str);
            for (j=0; str[j]&&str[j]!='='; ++j) {
                src[j] = getVal(str[j]);
            }
            l = decode(src, j);
            ac.create(buf, l, i);
        }
        ac.build();
        scanf("%d", &m);
        while (m--) {
            scanf("%s", str);
            for (j=0; str[j]; ++j) {
                if (str[j] == '=')
                    break;
                src[j] = getVal(str[j]);
            }
            l = decode(src, j);
            ac.query(buf, l);
            output(n);
        }
        printf("
");
    }

    return 0;
}