ZOJ 3430 Detect the Virus (AC automaton)

Title Link: Detect the Virus

Test instructions: N mode string, a text string, asking the text string contains several pattern strings.

Parsing: Decoding + AC automata.

Decoding process: The string is converted to ASCII and then converted to binary according to the corresponding ASCII, each is 6 bits, not enough to add 0, and then take 8 bits for a character, the string to be evaluated to be the string.

PS: note Sigma_size = 256

AC Code:

#include <bits/stdc++.h>using namespace std;struct trie{int next[520*64][256], fail[520*64], end[520*64];    int root, L;        int NewNode () {for (int i = 0; i <; i++) next[l][i] = 1;        end[l++] =-1;    return L-1;        } void Init () {L = 0;    root = NewNode ();        } void Insert (unsigned char buf[], int len, int id) {int now = root;            for (int i = 0; i < len; i++) {if (next[now][buf[i]] = = 1) next[now][buf[i]] = NewNode ();        now = next[now][Buf[i]];    } End[now] = ID;        } void Build () {queue<int> Q;        Fail[root] = root;            for (int i = 0; i < i++) {if (next[root][i] = = 1) next[root][i] = root;                else{fail[Next[root][i]] = root;            Q.push (Next[root][i]); }} while (!            Q.empty ()) {int now = Q.front ();            Q.pop ();             for (int i = 0; i < i++) {   if (next[now][i] = =-1) next[now][i] = next[Fail[now]][i];                    else{fail[next[now][i]] = next[Fail[now]][i];                Q.push (Next[now][i]);    }}}} bool used[520];        int query (unsigned char buf[], int len, int n) {memset (used, false, sizeof (used));        int now = root;            for (int i = 0; i < len; i++) {now = next[now][buf[i]];            int temp = now;                while (temp! = root) {if (end[temp]! =-1) used[end[temp]] = true;            temp = fail[temp];        }} int res = 0;        for (int i = 0; i < n; i++) if (Used[i]) res + +;    return res; }};unsigned Char buf[2050];int tot;char str[4000];unsigned Char s[4000];unsigned char Get (char ch) {if (ch >= ' A ' &am    p;& ch <= ' Z ') return CH-' A ';    if (Ch >= ' a ' && ch <= ' z ') return CH-' a ' + 26; if (ch >= ' 0 ' && ch <= ' 9') return CH-' 0 ' + 52;    if (ch = = ' + ') return 62; else return 63;}    void change (unsigned char str[], int len) {int t = 0; for (int i = 0; i < len; i+=4) {buf[t++] = ((str[i]<<2) |        (str[i+1]>>4)); if (I+2 < len) buf[t++] = ((str[i+1]<<4) |        (str[i+2]>>2)); if (I+3 < len) buf[t++] = ((str[i+2]<<6) |    (Str[i+3])); } tot = t;}    Trie Ac;int Main () {#ifdef sxk freopen ("In.txt", "R", stdin);    #endif//sxk int n, m;        while (scanf ("%d", &n) = = 1) {ac.init ();            for (int i = 0; i < n; i++) {scanf ("%s", str);            int len = strlen (str);            while (str[len-1] = = ') len--;            for (int j = 0; J < Len; j + +) S[j] = Get (Str[j]);            Change (S, Len);        Ac.insert (buf, tot, i);        } ac.build ();        scanf ("%d", &m);            while (M-) {scanf ("%s", str);            int len = strlen (str); while (StR[len-1] = = ' = ') len--;            for (int j = 0; J < Len; j + +) S[j] = Get (Str[j]);            Change (S, Len);        printf ("%d\n", Ac.query (buf, tot, n));    } puts (""); } return 0;}

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ZOJ 3430 Detect the Virus (AC automaton)