<p>Given a string array <code>words</code>, return <em>an array of all characters that show up in all strings within the </em><code>words</code><em> (including duplicates)</em>. You may return the answer in <strong>any order</strong>.</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>
<pre><strong>Input:</strong> words = ["bella","label","roller"]
<strong>Output:</strong> ["e","l","l"]
</pre><p><strong class="example">Example 2:</strong></p>
<pre><strong>Input:</strong> words = ["cool","lock","cook"]
<strong>Output:</strong> ["c","o"]
</pre>
<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= words.length &lt;= 100</code></li>
	<li><code>1 &lt;= words[i].length &lt;= 100</code></li>
	<li><code>words[i]</code> consists of lowercase English letters.</li>
</ul>

class Solution {
public:
    vector<string> commonChars(vector<string>& words) {

        int n = words.size();

        vector<int> hashMap(26,0);

        for(auto &c: words[0]){

            hashMap[c-'a']++;
            
        }

        for(int i=1;i<n;i++){

            vector<int> hashMap2(26,0);

            for(auto &c: words[i]){

                hashMap2[c-'a']++;
                
            }

            for(int j=0;j<26;j++){

                hashMap[j] = min(hashMap[j],hashMap2[j]);
                
            }
            
        }

        vector<string> result;

        for(int i=0;i<26;i++){

            while(hashMap[i]--){

                result.push_back(string(1,i+'a'));
                
            }
            
        }
        
        return result;
    }
};
12000