Singing Superstar HDU - 7064

Posted 2021-09-06 Jozky86

Singing Superstar HDU - 7064

题意：

问在串T中出现了几次不相交的串S？
每次有n个串S询问

题解：

AC自动机板子题。。
直接上模板

代码：

#include <bits/stdc++.h>
#include <unordered_map>
#define debug(a, b) printf("%s = %d\\n", a, b);
using namespace std;
const int maxnode= 5e5;
const int sigma_size= 26;
int ans= 0;
template <typename T> inline void read(T& x)
{
    T f= 1;
    x= 0;
    char ch= getchar();
    while (0 == isdigit(ch)) {
        if (ch == '-')
            f= -1;
        ch= getchar();
    }
    while (0 != isdigit(ch))
        x= (x << 1) + (x << 3) + ch - '0', ch= getchar();
    x*= f;
}
template <typename T> inline void write(T x)
{
    if (x < 0) {
        x= ~(x - 1);
        putchar('-');
    }
    if (x > 9)
        write(x / 10);
    putchar(x % 10 + '0');
}
struct AC_Automata
{
    int ch[maxnode][sigma_size];
    int val[maxnode]; // 以单词结尾的个数
    int f[maxnode]; // fail函数
    int last[maxnode]; // last[i]=j表j节点表示的单词是i节点单词的后缀，且j节点是单词节点
    int sz;
    int cnt[maxnode]; //非单词节点vis=0,单词节点vis=1.如果用find找到了单词i节点,那么vis=0.
    int pos[maxnode], len[maxnode];
    void init()
    {
        sz= 1;
        memset(ch[0], 0, sizeof(ch[0]));
        val[0]= 0;
        last[0]= f[0]= 0;
        memset(cnt, 0, sizeof(cnt));
        memset(pos, 0, sizeof(pos));
        memset(len, 0, sizeof(len));
    }

    void insert(char* s)
    {
        int n= strlen(s), u= 0;
        for (int i= 0; i < n; i++) {
            int id= s[i] - 'a';
            if (ch[u][id] == 0) {
                ch[u][id]= sz;

                memset(ch[sz], 0, sizeof(ch[sz]));
                val[sz++]= 0;
            }
            u= ch[u][id];
        }

        val[u]= 1;
        len[u]= n;
    }

    void getFail()
    {
        queue<int> q;
        last[0]= f[0]= 0;
        for (int i= 0; i < sigma_size; i++) {
            int u= ch[0][i];
            if (u) {
                f[u]= last[u]= 0;
                q.push(u);
            }
        }

        while (!q.empty()) {
            int r= q.front();
            q.pop();
            for (int i= 0; i < sigma_size; i++) {
                int u= ch[r][i];
                if (u == 0)
                    continue;
                q.push(u);

                int v= f[r];
                while (v && ch[v][i] == 0)
                    v= f[v];
                f[u]= ch[v][i];

                last[u]= val[f[u]] ? f[u] : last[f[u]];
            }
        }
    }
    void print(int i, int pos1)
    {
        if (val[i]) {
            if (pos[i] + len[i] <= pos1) {
                pos[i]= pos1;
                cnt[i]++;
            }
            print(last[i], pos1);
        }
    }
    void find(char* s)
    {
        int n= strlen(s), j= 0;
        for (int i= 0; i < n; i++) {
            int id= s[i] - 'a';
            while (j && ch[j][id] == 0)
                j= f[j];
            j= ch[j][id];
            if (val[j])
                print(j, i + 1);
            else if (last[j])
                print(last[j], i + 1);
        }
    }
    int find_T(char* s)
    {
        int n= strlen(s), u= 0;
        for (int i= 0; i < n; i++) {
            int id= s[i] - 'a';
            u= ch[u][id];
        }
        return cnt[u];
    }
};
AC_Automata ac;

char word[100080][50];
char s[100005];
int main()
{
    int n;
    int T;
    int cas= 0;
    read(T);
    while (T--) {
        scanf("%s", &s);
        scanf("%d", &n);
        ac.init();
        for (int i= 1; i <= n; i++) {
            scanf("%s", word[i]);
            ac.insert(word[i]);
        }
        ac.getFail();
        ac.find(s);
        for (int i= 1; i <= n; i++) {
            printf("%d\\n", ac.find_T(word[i]));
        }
    }
}