You are given a string allowed consisting of distinct characters and an array of strings words. A string is consistent if all characters in the string appear in the string allowed.
Return the number of consistent strings in the array words.
Example 1:
Input: allowed = "ab", words = ["ad","bd","aaab","baa","badab"] Output: 2 Explanation: Strings "aaab" and "baa" are consistent since they only contain characters 'a' and 'b'. Example 2:
Input: allowed = "abc", words = ["a","b","c","ab","ac","bc","abc"] Output: 7 Explanation: All strings are consistent. Example 3:
Input: allowed = "cad", words = ["cc","acd","b","ba","bac","bad","ac","d"] Output: 4 Explanation: Strings "cc", "acd", "ac", and "d" are consistent.
Constraints:
1 <= words.length <= 104 1 <= allowed.length <= 26 1 <= words[i].length <= 10 The characters in allowed are distinct. words[i] and allowed contain only lowercase English letters.
public class Solution {
public int CountConsistentStrings(string allowed, string[] words) {
var set = new HashSet<char>();
for(int i=0;i<allowed.Length;i++){
set.Add(allowed[i]);
}
int count = 0;
for(int i=0;i<words.Length;i++){
bool found = true;
for(int j=0;j<words[i].Length;j++){
if(!set.Contains(words[i][j])){
found = false;
break;
}
}
if(found){
count++;
}
}
return count;
}
}
Time Complexity: O(n*m)
Space Complexity: O(l)
Where n is the number of words, and m is the length of each word, while l is the length of the allowed word.


