Sukat

#include <bits/stdc++.h>

#define all(x) begin(x),end(x)
#define fi first
#define se second

using namespace std;
using ll = long long;
using pic = pair<int, char>;

void solve() {
    string s;
    cin >> s;

    int n = s.size();
    sort(all(s));

    vector<pair<char, char>> ans;
    
    do {
        vector<pair<char, char>> opt;
        int i = 0;
        while (i+1 < n) {
            if (s[i] != s[i+1]) {
                opt.push_back({s[i], s[i+1]});
                i += 2;
            } else ++i;
        }
        if (opt.size() > ans.size()) ans = opt;
    } while (next_permutation(all(s)));

    cout << ans.size() << '\n';
    for (auto &s : ans) cout << s.fi << s.se << '\n';
}

int main() {
    cin.tie(0) -> sync_with_stdio(0);

    solve();

    return 0;
}

Test 1

Group: 1, 2, 3

Verdict: ACCEPTED

Test 2

Group: 1, 2, 3

Verdict: ACCEPTED

Test 3

Group: 1, 2, 3

Verdict: ACCEPTED

Test 4

Group: 1, 2, 3

Verdict: ACCEPTED

Test 5

Group: 1, 2, 3

Verdict: ACCEPTED

Test 6

Group: 1, 2, 3

Verdict: ACCEPTED

Test 7

Group: 1, 2, 3

Verdict: ACCEPTED

Test 8

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 9

Group: 2, 3

Verdict: ACCEPTED

Test 10

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 12

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 13

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 14

Group: 2, 3

Verdict: TIME LIMIT EXCEEDED

Test 15

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 16

Group: 3

Verdict: ACCEPTED

Test 17

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 18

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 19

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 20

Group: 3

Verdict: TIME LIMIT EXCEEDED

Test 21

Group: 3

Verdict: TIME LIMIT EXCEEDED