Split in Three

#include <bits/stdc++.h>

using namespace std;

using ll = long long;

const int MAX_N = 100;
int p3[1 + MAX_N];

int main () {
    int n;
    cin >> n;
    p3[0] = 1;
    for (int i = 1; i <= n; i++)
        p3[i] = p3[i - 1] * 3;
    for (int mask = 0; mask < p3[n]; mask++) {
        vector <int> sum (3, 0);
        vector <int> values (n + 1);
        for (int pos = 0; pos < n; pos++) {
            int bucket = (mask / p3[pos]) % 3;
            sum[bucket] += pos + 1;
            values[pos + 1] = bucket + 1;
        }
        if (sum[0]  + 1 == sum[1] && sum[1] + 1 == sum[2]) {
            for (int i = 1; i <= n; i++)
                cout << values[i] << " ";
            cout << "\n";
            exit (0);
        }
    }
    cout << "IMPOSSIBLE\n";
    return 0;
}

Test 1

Group: 1, 2

Verdict: ACCEPTED

Test 2

Group: 1, 2

Verdict: ACCEPTED

Test 3

Group: 1, 2

Verdict: ACCEPTED

Test 4

Group: 1, 2

Verdict: ACCEPTED

Test 5

Group: 1, 2

Verdict: ACCEPTED

Test 6

Group: 1, 2

Verdict: ACCEPTED

Test 7

Group: 1, 2

Verdict: ACCEPTED

Test 8

Group: 1, 2

Verdict: ACCEPTED

Test 9

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 10

Group: 2

Verdict: TIME LIMIT EXCEEDED

Test 11

Group: 2

Verdict: WRONG ANSWER

Test 12

Group: 2

Verdict: ACCEPTED

Test 13

Group: 2

Verdict: WRONG ANSWER

Test 14

Group: 2

Verdict: WRONG ANSWER

Test 15

Group: 2

Verdict: ACCEPTED