1160. Find Words That Can Be Formed by Characters

You are given an array of strings words and a string chars.

A string is good if it can be formed by characters from chars (each character can only be used once).

Return the sum of lengths of all good strings in words.

 

Example 1:

Input: words = ["cat","bt","hat","tree"], chars = "atach"
Output: 6
Explanation: 
The strings that can be formed are "cat" and "hat" so the answer is 3 + 3 = 6.
Example 2:

Input: words = ["hello","world","leetcode"], chars = "welldonehoneyr"
Output: 10
Explanation: 
The strings that can be formed are "hello" and "world" so the answer is 5 + 5 = 10.
 

Note:

1 <= words.length <= 1000
1 <= words[i].length, chars.length <= 100
All strings contain lowercase English letters only.

这题也非常简单，给两个字符串做下计数，看看是否满足条件即可。

class FindWordsThatCanBeFormedByCharacters : public Solution {
public:
    void Exec() {

    }
    int countCharacters(vector<string>& words, string chars) {
        int char_count[26] = {0};
        for (int i = 0; i < chars.size(); i++) {
            char_count[chars[i] - 'a']++;
        }

        int result = 0;
        for (auto &str : words) {
            char sub_count[26] = {0};
            for (auto c : str) {
                sub_count[c - 'a']++;
            }
            bool match = true;
            for (int i = 0; i < 26; i++) {
                if (sub_count[i] == 0) {
                    continue;
                }
                if (sub_count[i] > char_count[i]) {
                    match = false;
                    break;
                }
            }
            if (match) {
                result += str.size();
            }
        }

        return result;
    }
};