Summat

input/code.cpp: In function 'bool ratkaise(int, int, std::vector<int>&, std::unordered_map<int, int>&)':
input/code.cpp:14:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
    for (int i = 0; i < luvut.size(); ++i) {
                    ~~^~~~~~~~~~~~~~
input/code.cpp: In function 'int main()':
input/code.cpp:44:6: warning: unused variable 'luvut_keskiarvo' [-Wunused-variable]
  int luvut_keskiarvo = luvut_yhteensa / n;
      ^~~~~~~~~~~~~~~

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

bool 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> tarjolla;
	for (int summa: summat_v) {
		int maara = summat_m[summa];
		while (tarjolla[summa] < maara) {
			int b = summa - luvut[0];
			for (int i = 0; i < luvut.size(); ++i) {
				int c = b + luvut[i];
				tarjolla[c] += 1;
				if (tarjolla[c] > summat_m[c]) {
					return false;
				}
			}
			luvut.push_back(b);
		}
	}
	for (int luku: luvut) {
		std::cout << luku << ' ';
	}
	std::cout << '\n';
	return true;
}

int main() {
	int n;
	std::cin >> n;
	std::vector<int> summat(n * (n-1) / 2);
	std::set<int> summat_s;
	std::unordered_map<int, int> summat_m;
	long summat_yhteensa = 0;
	for (auto& k: summat) {
		std::cin >> k;
		summat_m[k] += 1;
		summat_yhteensa += k;
	}
	long luvut_yhteensa = summat_yhteensa / (n-1);
	int luvut_keskiarvo = luvut_yhteensa / n;
	for (auto s: summat_m) {
		summat_s.insert(s.first);
	}
	std::vector<int> summat_v(summat_s.begin(), summat_s.end());
	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;
		int a = aa / 2;
		if ((aa & 1) == 0 && ratkaise(a, n, summat_v, summat_m)) {
			break;
		}
	}
}

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