<p>Two strings, <code>X</code> and <code>Y</code>, are considered similar if either they are identical or we can make them equivalent by swapping at most two letters (in distinct positions) within the string <code>X</code>.</p>

<p>For example, <code>&quot;tars&quot;</code>&nbsp;and <code>&quot;rats&quot;</code>&nbsp;are similar (swapping at positions <code>0</code> and <code>2</code>), and <code>&quot;rats&quot;</code> and <code>&quot;arts&quot;</code> are similar, but <code>&quot;star&quot;</code> is not similar to <code>&quot;tars&quot;</code>, <code>&quot;rats&quot;</code>, or <code>&quot;arts&quot;</code>.</p>

<p>Together, these form two connected groups by similarity: <code>{&quot;tars&quot;, &quot;rats&quot;, &quot;arts&quot;}</code> and <code>{&quot;star&quot;}</code>.&nbsp; Notice that <code>&quot;tars&quot;</code> and <code>&quot;arts&quot;</code> are in the same group even though they are not similar.&nbsp; Formally, each group is such that a word is in the group if and only if it is similar to at least one other word in the group.</p>

<p>We are given a list <code>strs</code> of strings where every string in <code>strs</code> is an anagram of every other string in <code>strs</code>. How many groups are there?</p>

<p>&nbsp;</p>
<p><strong class="example">Example 1:</strong></p>

<pre>
<strong>Input:</strong> strs = [&quot;tars&quot;,&quot;rats&quot;,&quot;arts&quot;,&quot;star&quot;]
<strong>Output:</strong> 2
</pre>

<p><strong class="example">Example 2:</strong></p>

<pre>
<strong>Input:</strong> strs = [&quot;omv&quot;,&quot;ovm&quot;]
<strong>Output:</strong> 1
</pre>

<p>&nbsp;</p>
<p><strong>Constraints:</strong></p>

<ul>
	<li><code>1 &lt;= strs.length &lt;= 300</code></li>
	<li><code>1 &lt;= strs[i].length &lt;= 300</code></li>
	<li><code>strs[i]</code> consists of lowercase letters only.</li>
	<li>All words in <code>strs</code> have the same length and are anagrams of each other.</li>
</ul>

class Solution {
    vector<int>parent;
    vector<int>size;
    void make(int node){
        parent[node]=node;
        size[node]=node;
    }
    void Union(int u,int v){
        int a=find(u);
        int b=find(v);
        if(size[a]<size[b]){
            swap(a,b);
        }
        if(a!=b){
            parent[b]=a;
            size[a]+=size[b];
        }
    }
    int find(int node){
        if(parent[node]==node)return node;
        return parent[node]=find(parent[node]);
    }
public:
    int numSimilarGroups(vector<string>& strs) {
        int n=strs.size();
        int m=strs[0].size();
        parent.resize(n);
        size.resize(n);
        for(int i=0;i<n;i++){
            make(i);
        }
        for(int i=0;i<n;i++){
            string a=strs[i];
            for(int j=i+1;j<n;j++){
                string b=strs[j];
                int count=0;
                for(int k=0;k<m;k++){
                    if(a[k]!=b[k])count++;
                }
                if(count==2 || count==0)Union(i,j);
            }
        }
        int ans=0;
        for(int i=0;i<n;i++){
            if(parent[i]==i )ans++;
        }
        return ans;
    }
};
65026