Submission #572868

#	Time	Username	Problem	Language	Result	Execution time	Memory
572868		vovamr	Gift (IZhO18_nicegift)	C++17	7 / 100	1953 ms	524288 KiB

nicegift

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#define fi first
#define se second
#define ll long long
#define ld long double
#define sz(x) ((int)(x).size())
#define all(x) 	(x).begin(), (x).end()
#define pb push_back
#define mpp make_pair
#define ve vector
using namespace std;
using namespace __gnu_pbds;
template<class T> using oset = tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;
const ll inf = 1e18; const int iinf = 1e9;
typedef pair<ll, ll> pll;
typedef pair<int, int> pii;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());
template <typename T> inline bool chmin(T& a, T b) { return (a > b ? a = b, 1 : 0); }
template <typename T> inline bool chmax(T& a, T b) { return (a < b ? a = b, 1 : 0); }

inline void solve() {
	int n, k;
	cin >> n >> k;
	ve<int> a(n);

	ll s = 0;
	set<pii> st;
	for (int i = 0; i < n; ++i) {
		cin >> a[i];
		st.insert({a[i], i});
		s += a[i];
	}

	if (s % k || (*st.rbegin()).fi > s / k) return void(cout << -1);

	ve<pair<int,ve<int>>> answer;

	while (sz(st)) {
		ve<pii> ind;
		for (int i = 0; i < k; ++i) {
			ind.pb(*--st.end());
			st.erase(--st.end());
		}

		ll add = ind.front().fi;
		if (sz(st)) chmin(add, s / k - (*--st.end()).fi);

		answer.pb({add, {}});
		for (auto &[_, i] : ind) {
			s -= add, a[i] -= add;
			if (a[i]) st.insert({a[i], i});
			answer.back().se.pb(i);
		}
	}
	cout << sz(answer) << '\n';
	for (auto &[add, vec] : answer) {
		cout << add << " ";
		for (auto i : vec) cout << i + 1 << " ";
		cout << '\n';
	}
}

signed main() {
	ios_base::sync_with_stdio(false); cin.tie(0); cout.tie(0);
	int q = 1; // cin >> q;
	while (q--) solve();
	cerr << fixed << setprecision(3) << "Time execution: " << (double)clock() / CLOCKS_PER_SEC << endl;
}

• Subtask 1: 7 / 7
• Subtask 2: 0 / 11
• Subtask 3: 0 / 12
• Subtask 4: 0 / 19
• Subtask 5: 0 / 51