<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) {
        unordered_map<char, int> mp;
        unordered_map<char, int> nxt;

        for (int i = 0; i < words.size(); i++) {
            for (char c : words[i]) {
                nxt[c]++;
            }
            if (i == 0) {
                mp = nxt;
            }
            else {
                for (auto &e : mp) {
                    if (nxt.find(e.first) != nxt.end()){
                        e.second = min(e.second, nxt[e.first]);
                    }
                    else {
                        e.second = 0;
                    }
                }
            }
            nxt.clear();
        }
        vector<string> ans;
        for (auto &e : mp) {
            for (int i = 0; i < e.second; i++) {
                ans.push_back(string() + e.first);
            }
        }
        return ans;}
    
};
13600