Submission #395273

#	Time	Username	Problem	Language	Result	Execution time	Memory
395273		rama_pang	Gift (IZhO18_nicegift)	C++17	100 / 100	683 ms	124628 KiB

nicegift

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

int main() {
  ios::sync_with_stdio(0);
  cin.tie(0), cout.tie(0);

  int N, K;
  cin >> N >> K;

  lint total = 0;
  vector<lint> A(N);
  for (int i = 0; i < N; i++) {
    cin >> A[i];
    total += A[i];
  }

  if (total % K != 0 || total / K < *max_element(begin(A), end(A))) {
    cout << -1 << "\n";
    return 0;
  }

  lint limit = total / K;
  vector<lint> sum(K);
  vector<vector<pair<lint, int>>> data(K);

  for (int i = 0; i < N; i++) {
    for (int j = 0; j < K && A[i] > 0; j++) {
      if (sum[j] + A[i] <= limit) {
        sum[j] += A[i];
        data[j].emplace_back(A[i], i);
        A[i] = 0;
      } else if (sum[j] < limit) {
        A[i] -= limit - sum[j];
        data[j].emplace_back(limit - sum[j], i);
        sum[j] = limit;
      }
    }
    assert(A[i] == 0);
  }

  vector<pair<lint, vector<int>>> ans;
  while (!data[0].empty()) {
    lint minim = 1e18;
    for (int i = 0; i < K; i++) {
      minim = min(minim, data[i].back().first);
    }
    ans.emplace_back();
    ans.back().first = minim;
    for (int i = 0; i < K; i++) {
      ans.back().second.emplace_back(data[i].back().second);
      data[i].back().first -= minim;
      if (data[i].back().first == 0) {
        data[i].pop_back();
      }
    }
  }

  assert(ans.size() <= N);
  cout << ans.size() << "\n";
  for (auto i : ans) {
    cout << i.first;
    for (auto j : i.second) {
      cout << " " << j + 1;
    }
    cout << "\n";
  }
  return 0;
}

Compilation message (stderr)

In file included from /usr/include/c++/9/cassert:44,
                 from /usr/include/x86_64-linux-gnu/c++/9/bits/stdc++.h:33,
                 from nicegift.cpp:1:
nicegift.cpp: In function 'int main()':
nicegift.cpp:60:21: warning: comparison of integer expressions of different signedness: 'std::vector<std::pair<long long int, std::vector<int> > >::size_type' {aka 'long unsigned int'} and 'int' [-Wsign-compare]
   60 |   assert(ans.size() <= N);
      |          ~~~~~~~~~~~^~~~

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