AcWing 142. 前綴統計——（trie字典樹-模板題）

總結

用數組模擬，感覺更直觀，代碼更簡潔吧

題目鏈接

//#pragma GCC optimize(2)
#include<bits/stdc++.h>
//typedef long long ll;
#define ull       unsigned long long
#define int       long long
#define F           first
#define S           second
#define endl        "\n"//<<flush
#define eps         1e-6
#define base        131
#define lowbit(x)   (x&(-x))
#define PI          acos(-1.0)
#define inf         0x3f3f3f3f
#define MAXN        0x7fffffff
#define INF         0x3f3f3f3f3f3f3f3f
#define ferma(a,b)  pow(a,b-2)
#define pb          push_back
#define all(x)      x.begin(),x.end()
#define memset(a,b) memset(a,b,sizeof(a));
#define IOS         ios::sync_with_stdio(false),cin.tie(0),cout.tie(0);
using namespace std;
void file()
{
#ifdef ONLINE_JUDGE
#else
    freopen("D:/LSNU/codeforces/duipai/data.txt","r",stdin);
    //  freopen("D:/LSNU/codeforces/duipai/WA.txt","w",stdout);
#endif
}
const int N=1e6+5;
int son[N][26],cnt[N],pos;
void insert(string &str)
{
    int p=0;
    for(auto it:str)
    {
        int &temp=son[p][it-'a'];
        if(!temp)
            temp=++pos;
        p=temp;
    }
    cnt[p]++;
}
int query(string &str)
{
    int sum=0,p=0;
    for(auto it:str)
    {
        int &temp=son[p][it-'a'];
        if(!temp)
            break;
        p=temp;
        sum+=cnt[p];
    }
    return sum;
}
signed main()
{
    IOS;
    // file();
    int n,m;
    cin>>n>>m;
    while(n--)
    {
        string str;
        cin>>str;
        insert(str);
    }
    while(m--)
    {
        string str;
        cin>>str;
        cout<<query(str)<<endl;
    }
    return 0;
}