Anagrams

input/code.cpp: In function 'int main()':
input/code.cpp:64:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
             for(int j=0;j<res[i].size();++j){
                         ~^~~~~~~~~~~~~~

#include <bits/stdc++.h>

using namespace std;

pair<string,string> tab2[4000100];
vector<string> res[4000100];

int main()
{
    int n;
    string s;
    cin >> n;
    for(int i=0; i<n;++i){
        cin >> s;
        tab2[i].first=s;
        tab2[i].second=s;
        sort(tab2[i].first.begin(),tab2[i].first.end());
    }
    sort(tab2,tab2+n);
    /*for( int i=0;i<n;++i)
    {
        cout << tab2[i].first << " , " << tab2[i].second << endl;
    }*/
    int groups=0;
    int group_count=1;
    res[0].push_back(tab2[0].second);
    string prev=tab2[0].first;
    for(int i=1; i<n-1; ++i){
        if(tab2[i].first==prev){
            group_count++;
            res[groups].push_back(tab2[i].second);
        }else{
        if(group_count>1){
            groups++;
            prev=tab2[i].first;
            res[groups].push_back(tab2[i].second);
            group_count=1;
        }else{
            res[groups].pop_back();
            res[groups].push_back(tab2[i].second);
            group_count=1;
            prev=tab2[i].first;
        }
        }
    }
    if(n>1){
    if(tab2[n-1].first==prev){
            group_count++;
            res[groups].push_back(tab2[n-1].second);
            groups++;
        }else{
        if(group_count>1){
            groups++;
        }else{
            res[groups].pop_back();
        }
        }
    }

        cout << groups << endl;
        for(int i=0; i<groups;i++)
        {
            cout << res[i].size() << endl;
            for(int j=0;j<res[i].size();++j){
            cout << res[i][j] << endl;
            }
        }
    return 0;
}

Test 1

Verdict: ACCEPTED

Test 2

Verdict: ACCEPTED

Test 3

Verdict: ACCEPTED

Test 4

Verdict: ACCEPTED

Test 5

Verdict: ACCEPTED

Test 6

Verdict: ACCEPTED

Test 7

Verdict: ACCEPTED

Test 8

Verdict: ACCEPTED

Test 9

Verdict: ACCEPTED