HDU 2222 Keywords Search AC自动机

单词会重复,累加完一个的单词后把val清0,避免重复计算。

//#pragma comment(linker, "/STACK:1024000000,1024000000")
#include<cstdio>
#include<cstring>
#include<cstdlib>
#include<algorithm>
#include<iostream>
#include<sstream>
#include<cmath>
#include<climits>
#include<string>
#include<map>
#include<queue>
#include<vector>
#include<stack>
#include<set>
using namespace std;
typedef long long ll;
typedef pair<int,int> pii;
#define pb(a) push_back(a)
#define INF 0x1f1f1f1f
#define lson idx<<1,l,mid
#define rson idx<<1|1,mid+1,r
#define PI  3.1415926535898
template<class T> T min(const T& a,const T& b,const T& c) {
    return min(min(a,b),min(a,c));
}
template<class T> T max(const T& a,const T& b,const T& c) {
    return max(max(a,b),max(a,c));
}
void debug() {
#ifdef ONLINE_JUDGE
#else

    freopen("d:\in.txt","r",stdin);
   // freopen("d:\out1.txt","w",stdout);
#endif
}
int getch() {
    int ch;
    while((ch=getchar())!=EOF) {
        if(ch!=' '&&ch!='
')return ch;
    }
    return EOF;
}

const int MAX_NODE=251000;
const int SIGMA_SIZE=26;
struct ac_automation
{
    int sz;
    int ch[MAX_NODE][SIGMA_SIZE];
    int f[MAX_NODE];
    //int last[MAX_NODE];
    int val[MAX_NODE];
    void init(){
        sz=0;
        memset(ch,0,sizeof(ch));
        memset(val,0,sizeof(val));
    }
    int idx(char c){return c-'a';}
    int insert(const char *s)
    {
        int u=0;
        for(int i=0;s[i]!='';i++)
        {
            int v=idx(s[i]);
            if(!ch[u][v])ch[u][v]=++sz;
            u=ch[u][v];
        }
        val[u]++;
        return 0;
    }
    void build()
    {
        queue<int> q;
        f[0]=0;
        for(int c=0;c<SIGMA_SIZE;c++)
        {
            int u=ch[0][c];
            if(u){f[u]=0;q.push(u);}
        }
        while(!q.empty())
        {
            int r=q.front();q.pop();
            for(int c=0;c<SIGMA_SIZE;c++)
            {
                int u=ch[r][c];
                if(!u){ch[r][c]=ch[f[r]][c];continue;}
                q.push(u);
                int v=f[r];
                while(v&&!ch[v][c])v=f[v];
                f[u]=ch[v][c];
            }
        }
    }
    int count(int j,int &num)
    {
        if(val[j])
        {
            num+=val[j];
            val[j]=0;
            count(f[j],num);
        }
        return 0;
    }
    int find(const char *T)
    {
        int num=0;
        int j=0;
        for(int i=0;T[i]!='';i++)
        {
            int c=idx(T[i]);
            //while(j&&!ch[j][c])j=f[j];
            j=ch[j][c];
            if(j)count(j,num);

        }
        return num;
    }
}AC;

char T[1001000];
int main()
{
    int t;
    scanf("%d",&t);
    for(int ca=1;ca<=t;ca++)
    {
        int n;
        scanf("%d",&n);
       // ac_automation AC;
        AC.init();
        for(int i=1;i<=n;i++)
        {
            char s[60];
            scanf("%s",s);
            AC.insert(s);
        }
        AC.build();
        scanf("%s",T);
        int num=AC.find(T);
        printf("%d
",num);
    }
    return 0;
}
View Code
原文地址:https://www.cnblogs.com/BMan/p/3372880.html