Codeforces Round #291 (Div. 2) C Watto and Mechanism

思路：直接搞个字典树就好啦

#include<bits\stdc++.h>using namespace std;struct trie {    int nxt[3], ep;    trie(){        memset(nxt, -1, sizeof nxt);        ep = 0;    }}ar[2000001];char pp[600011];int cnt = 0;void insert(char *s, int idx){    if(s[0] == '\0'){        ar[idx].ep = 1;        return;    }    int x = s[0] - 'a';    if(ar[idx].nxt[x] == -1) {        cnt++;        ar[cnt] = trie();        ar[idx].nxt[x] = cnt;    }    insert(s + 1, ar[idx].nxt[x]);}int query(char *s, int idx, int q){    if(s[0] == '\0'){        if(q == 1 && ar[idx].ep == 1) return 1;        return 0;    }    int x = s[0] - 'a';    for(int i = 0;i<3;i++){        if(i != x && q == 0 && ar[idx].nxt[i] != -1)   {            if(query(s + 1, ar[idx].nxt[i], 1)) return 1;        }        if(i == x && ar[idx].nxt[x] != -1){            if(query(s + 1, ar[idx].nxt[x], q)) return 1;        }    }    return 0;}int main() {    ios_base::sync_with_stdio(0); cin.tie(0);    int n, m; cin >> n >> m;    ar[0] = trie();    for(int i = 0;i<n;i++){        cin >> pp;        insert(pp, 0);    }    for(int i = 0;i<m;i++){        cin >> pp;        if(query(pp, 0, 0) == 1) cout << "YES" << endl;        else cout << "NO" << endl;    }}

C. Watto and Mechanism

time limit per test

3 seconds

memory limit per test

256 megabytes

input

standard input

output

standard output

Watto, the owner of a spare parts store, has recently got an order for the mechanism that can process strings in a certain way. Initially the memory of the mechanism is filled with n strings. Then the mechanism should be able to process queries of the following type: "Given string s, determine if the memory of the mechanism contains string t that consists of the same number of characters as s and differs from s in exactly one position".

Watto has already compiled the mechanism, all that's left is to write a program for it and check it on the data consisting of n initial lines and m queries. He decided to entrust this job to you.

Input

The first line contains two non-negative numbers n and m (0 ≤ n ≤ 3·105, 0 ≤ m ≤ 3·105) — the number of the initial strings and the number of queries, respectively.

Next follow n non-empty strings that are uploaded to the memory of the mechanism.

Next follow m non-empty strings that are the queries to the mechanism.

The total length of lines in the input doesn't exceed 6·105. Each line consists only of letters 'a', 'b', 'c'.

Output

For each query print on a single line "YES" (without the quotes), if the memory of the mechanism contains the required string, otherwise print "NO" (without the quotes).

Examples

input

2 3aaaaaacacacaaabaaccacacccaaac

output

YESNONO