Question
You have a list of words
and a pattern
, and you want to know which words in words
matches the pattern.
A word matches the pattern if there exists a permutation of letters p
so that after replacing every letter x
in the pattern with p(x)
, we get the desired word.
(Recall that a permutation of letters is a bijection from letters to letters: every letter maps to another letter, and no two letters map to the same letter.)
Return a list of the words in words
that match the given pattern.
You may return the answer in any order.
Example 1:
Input: words = ["abc","deq","mee","aqq","dkd","ccc"], pattern = "abb" Output: ["mee","aqq"] Explanation: "mee" matches the pattern because there is a permutation {a -> m, b -> e, ...}. "ccc" does not match the pattern because {a -> c, b -> c, ...} is not a permutation, since a and b map to the same letter.
Note:
1 <= words.length <= 50
1 <= pattern.length = words[i].length <= 20
Solution
class Solution {
public:
vector<string> findAndReplacePattern(vector<string>& words, string pattern) {
vector<string> res;
for (auto w : words) {
string s = w;
vector<int> vec(127), vec_p(127);
for (char c : pattern) vec_p[c] = 1;
for (int i = 0; i < s.size(); ++i) {
if (vec[s[i]] == 0 && vec_p[pattern[i]] == 1) {
vec[s[i]] = pattern[i];
vec_p[pattern[i]] = 0;
}
}
for (int i = 0; i < s.size(); ++i) {
if (vec[s[i]]) s[i] = vec[s[i]];
}
if (s == pattern) res.push_back(w);
}
return res;
}
};