<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 DisjointSet{
    public:
    vector<int> parent;
    vector<int> rank;
    DisjointSet(int n){
        parent.resize(n);
        rank.resize(n,0);
        for(int i=0;i<n;i++){
            parent[i]=i;
        }
    }
    int findParent(int x){
        if(x==parent[x]){
            return x;
        }
        return parent[x]=findParent(parent[x]);
    }
    void unionRank(int x,int y){
        int px=findParent(x);
        int py=findParent(y);
        if(px==py){
            return;
        }
        if(rank[px]>rank[py]){
            parent[py]=px;
        }else if(rank[px]<rank[py]){
            parent[px]=py;
        }else{
            parent[px]=py;
            rank[py]++;
        }
    }
};
class Solution {
private:
    bool isSimilar(string curr1,string curr2){
        int diff=0;
        for(int i=0;i<curr1.length();i++){
            if(curr1[i]!=curr2[i]){
                diff++;
            }
        }
        if(diff==2||diff==0){
            return true;
        }else{
            return false;
        }
    }
public:
    int numSimilarGroups(vector<string>& strs) {
        int n=strs.size();
        DisjointSet ds(n);
        unordered_map<string,int> mp;
        for(int i=0;i<n;i++){
            mp[strs[i]]=i;
        }
        for(int i=0;i<n;i++){
            string curr1=strs[i];
            for(int j=i+1;j<n;j++){
                string curr2=strs[j];
                if(isSimilar(curr1,curr2)){
                    ds.unionRank(i,j);
                }
            }
        }
        int ct=0;
        for(int i=0;i<n;i++){
            if(ds.parent[i]==i){
                ct++;
            }
        }
        return ct;
    }
};
162021