Submission #378929

#	Time	Username	Problem	Language	Result	Execution time	Memory
378929		cheissmart	Gift (IZhO18_nicegift)	C++14	0 / 100	736 ms	114200 KiB

nicegift

#include <bits/stdc++.h>
#define IO_OP std::ios::sync_with_stdio(0); std::cin.tie(0);
#define F first
#define S second
#define V vector
#define PB push_back
#define MP make_pair
#define EB emplace_back
#define ALL(v) (v).begin(), (v).end()
#define debug(x) cerr << "Line(" << __LINE__ << ") -> " << #x << " is " << x << endl

using namespace std;

typedef long long ll;
typedef pair<int, int> pi;
typedef V<int> vi;

const int INF = 1e9 + 7, N = 1e6 + 7;

ll a[N];

signed main()
{
	IO_OP;

	int n, k;
	cin >> n >> k;
	ll sum = 0, mx = 0;
	for(int i = 0; i < n; i++) {
		cin >> a[i];
		sum += a[i];
		mx = max(mx, a[i]);
	}
	if(sum % k || mx > sum / k) {
		cout << -1 << '\n';
		return 0;
	}
	V<array<ll, 3>> ev;
	auto add_event = [&] (ll l, ll r, int i) { // [l, r)
		assert(l < r);
		ev.PB({l, 1, i});
		ev.PB({r, -1, i});
	};
	ll psum = 0;
	for(int i = 0; i < n; i++) {
		if(a[i] >= sum / k) add_event(0, sum / k, i + 1); // [l, r)
		else {
			ll lb = psum % (sum / k), rb = (lb + a[i] - 1) % (sum / k);
			if(lb > rb) swap(lb, rb);
			add_event(lb, rb + 1, i + 1);
		}
		psum += a[i];
	}
	sort(ALL(ev));
	set<int> who;
	int lst = -1;
	V<ll> ans;
	for(auto e:ev) {
		if(lst != -1 && e[0] != lst) {
			assert(int(who.size()) == k);
			ll x = e[0] - lst;
			ans.PB(x);
			for(int i:who)
				ans.PB(i);
		}
		if(e[1] == 1) { // add
			assert(who.count(e[2]) == 0);
			who.insert(e[2]);
		} else {
			assert(who.count(e[2]) == 1);
			who.erase(e[2]);
		}
		assert(int(who.size()) <= k);
		lst = e[0];
	}
	cout << int(ans.size()) / (k + 1) << '\n';
	for(int i = 0; i < int(ans.size()); i++)
		cout << ans[i] << " \n"[i % (k + 1) == k];

}

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