Sukat

#include <bits/stdc++.h>

using namespace std;
using ll = int64_t;

int main() {
    string s;
    cin >> s;

    ll c = 0;
    stringstream ss;
    unordered_map<char, ll> mm;
    for(auto c : s) 
        mm[c]++;

    while(!mm.empty() && mm.size() != 1) {
        for(auto& e : mm) {
            for(auto& e2 : mm) {
                if(e.first != e2.first) {
                    e2.second--;
                    e.second--;
                    c++;
                    ss << e.first << e2.first << "\n";
                    if(e2.second == 0)
                        mm.erase(e.first);

                    break;
                }
            }
            if(e.second == 0)
                mm.erase(e.first);
            break;
        }
    }
    cout << c << "\n";
    cout << ss.str();
}

Test 1

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 5

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 6

Group: 1, 2, 3

Verdict: WRONG ANSWER

Test 7

Group: 1, 2, 3

Verdict: ACCEPTED

Test 8

Group: 2, 3

Verdict: WRONG ANSWER

Test 9

Group: 2, 3

Verdict: ACCEPTED

Test 10

Group: 2, 3

Verdict: WRONG ANSWER

Test 11

Group: 2, 3

Verdict: WRONG ANSWER

Test 12

Group: 2, 3

Verdict: WRONG ANSWER

Test 13

Group: 2, 3

Verdict: WRONG ANSWER

Test 14

Group: 2, 3

Verdict: WRONG ANSWER

Test 15

Group: 3

Verdict: WRONG ANSWER

Test 16

Group: 3

Verdict: ACCEPTED

Test 17

Group: 3

Verdict: WRONG ANSWER

Test 18

Group: 3

Verdict: WRONG ANSWER

Test 19

Group: 3

Verdict: WRONG ANSWER

Test 20

Group: 3

Verdict: WRONG ANSWER

Test 21

Group: 3

Verdict: WRONG ANSWER