Summat

#include <iostream>
#include <vector>
#include <unordered_map>
#include <algorithm>

std::vector<int> ratkaise(int a, int n, std::vector<int>& summat_v, std::unordered_map<int, int>& summat_m) {
	std::vector<int> luvut {a};
	std::unordered_map<int, int> omat_summat;
	for (int summa: summat_v) {
		int maara = summat_m[summa];
		while (omat_summat[summa] < maara) {
			int b = summa - luvut[0];
			for (int i: luvut) {
				int c = b + i;
				omat_summat[c] += 1;
				if (omat_summat[c] > summat_m[c]) {
					return {};
				}
			}
			luvut.push_back(b);
		}
	}
	return luvut;
}

int main() {
	int n;
	std::cin >> n;

	std::unordered_map<int, int> summat_m;
	for (int i = n * (n-1) / 2, k; i--;) {
		std::cin >> k;
		summat_m[k] += 1;
	}

	std::vector<int> summat_v;
	for (auto s: summat_m) {
		summat_v.push_back(s.first);
	}
	std::sort(summat_v.begin(), summat_v.end());

	std::vector<int> luvut;
	long ab = summat_v[0];
	long ac = summat_v[summat_m[ab] > 1 ? 0 : 1];
	for (long bc: summat_v) {
		int aa = ab + ac - bc;
		luvut = ratkaise(aa / 2, n, summat_v, summat_m);
		if (luvut.size()) {
			break;
		}
	}

	for (int luku: luvut) {
		std::cout << luku << ' ';
	}
	std::cout << '\n';
}

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: 2, 3

Verdict: ACCEPTED

Test 7

Group: 2, 3

Verdict: ACCEPTED

Test 8

Group: 2, 3

Verdict: ACCEPTED

Test 9

Group: 2, 3

Verdict: ACCEPTED

Test 10

Group: 2, 3

Verdict: ACCEPTED

Test 11

Group: 3

Verdict: ACCEPTED

Test 12

Group: 3

Verdict: ACCEPTED

Test 13

Group: 3

Verdict: ACCEPTED

Test 14

Group: 3

Verdict: ACCEPTED

Test 15

Group: 3

Verdict: ACCEPTED