Codeforces Round #291 (Div. 2),
C. Watto and Mechanismtime limit per test3 secondsmemory limit per test256 megabytesinputstandard inputoutputstandard 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 froms 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).
Sample test(s)input
2 3aaaaaacacacaaabaaccacacccaaac
output
YESNONO
思路:剛開始我還以為是Trie樹,,然後慢慢的敲。。。最後發現暴力就可以了,,而且貌似很多人用hash做得,,不太會,,以後再慢慢來try吧。。這題先暴力解決掉
暴力的AC代碼:
#include <cstdio>#include <cstring>#include <iostream>#include <algorithm>#include <set>#define LL long longusing namespace std;int main() {int n, m;while(scanf("%d %d", &n, &m) != EOF) {set<string> a;LL maxn = 0;for(int i = 0; i < n; i++) {string tmp;cin >> tmp;a.insert(tmp);if((int)tmp.size() > maxn) maxn = tmp.size();}if(m * n * maxn < 100000000) {for(int i = 0 ; i < m; i++) {string tmp;cin >> tmp;bool flag = false;for(set<string>::iterator it = a.begin(); it != a.end() && !flag; it++) {if(it->size() == tmp.size()) {int cnt = 0;for(int j = 0; j < it->size(); j++) {if((*it)[j] != tmp[j]) cnt++;}if(cnt == 1) flag = true;}}if(flag) printf("YES\n");else printf("NO\n");}continue;}for(int i = 0; i < m; i++) {string tmp;cin >> tmp;bool flag = false;for(int j = 0; j < tmp.size() && !flag; j++) {if(tmp[j] == 'a') {tmp[j] = 'b';if(a.find(tmp) != a.end()) flag = true;tmp[j] = 'c';if(a.find(tmp) != a.end()) flag = true;tmp[j] = 'a';}else if(tmp[j] == 'b') {tmp[j] = 'c';if(a.find(tmp) != a.end()) flag = true;tmp[j] = 'a';if(a.find(tmp) != a.end()) flag = true;tmp[j] = 'b';}else if(tmp[j] == 'c') {tmp[j] = 'a';if(a.find(tmp) != a.end()) flag = true;tmp[j] = 'b';if(a.find(tmp) != a.end()) flag = true;tmp[j] = 'c';}}if(flag) printf("YES\n");else printf("NO\n");}}return 0;}