Submission #41161

#	Time	Username	Problem	Language	Result	Execution time	Memory
41161		aome	Gift (IZhO18_nicegift)	C++14	100 / 100	783 ms	168880 KiB

nicegift

#include <bits/stdc++.h>
using namespace std;

const int N = 1000005;

int n, k;
long long sum, mx, a[N];
vector< vector< pair<long long, int> > > blocks;
vector< vector<long long> > res;

int main() {
	ios::sync_with_stdio(false);
	cin >> n >> k;
	for (int i = 1; i <= n; ++i) {
		cin >> a[i], sum += a[i], mx = max(mx, a[i]);
	}
	if (sum % k || mx > sum / k) {
		cout << -1; return 0;
	}
	long long avg = sum / k;
	long long cur = 0;
	vector< pair<long long, int > > vec;
	for (int i = 1; i <= n; ++i) {
		cur += a[i];
		if (cur >= avg) {
			vec.push_back(make_pair(a[i] - (cur - avg), i));
			blocks.push_back(vec), vec.clear(), cur -= avg;
			if (cur) {
				vec.push_back(make_pair(cur, i));
			} 
		}
		else vec.push_back(make_pair(a[i], i));
	}
/*	for (int i = 0; i < k; ++i) {
		cout << "#" << i << '\n';
		for (auto j : blocks[i]) cout << j.first << ' ' << j.second << '\n';
	}*/
	while (sum) {
		long long mn = 1e18;
		for (int i = 0; i < k; ++i) {
			mn = min(mn, blocks[i].back().first);
		}
		sum -= mn * k;
		vector<long long> vec;
		vec.push_back(mn);
		for (int i = 0; i < k; ++i) {
			blocks[i][blocks[i].size() - 1].first -= mn;
			vec.push_back(blocks[i].back().second);
			if (!blocks[i].back().first) blocks[i].pop_back();
		}
		res.push_back(vec);
	}
	cout << res.size() << '\n';
	for (int i = 0; i < res.size(); ++i) {
		for (auto j : res[i]) cout << j << ' '; cout << '\n';
	}
}

Compilation message (stderr)

nicegift.cpp: In function 'int main()':
nicegift.cpp:54:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
  for (int i = 0; i < res.size(); ++i) {
                    ^

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