Submission #721038

#	Time	Username	Problem	Language	Result	Execution time	Memory
721038		cig32	Gift (IZhO18_nicegift)	C++17	30 / 100	780 ms	106008 KiB

nicegift

#include "bits/stdc++.h"
#define int long long
using namespace std;
const int MAXN = 1e5 + 10;
void solve(int tc) {
  int n, k;
  cin >> n >> k;
  priority_queue<pair<int,int> > pq;
  int a[n+1];
  for(int i=1; i<=n; i++) {
    cin >> a[i];
    pq.push({a[i], i});
  }
  if(k == n) {
    for(int i=1; i<n; i++){
      if(a[i] != a[i+1]) {
        cout << "-1\n"; return;
      }
    }
    cout << "1\n";
    cout << a[1];
    for(int i=1; i<=n; i++) cout << " " << i;
    cout << '\n';
    return;
  }
  int lim = 3000000 / k;
  vector<vector<int> > ops;
  while(lim--) {
    while(pq.size() && pq.top().first == 0) pq.pop();
    if(pq.empty()) break;
    if(pq.size() < k) {
      cout << "-1\n"; return;
    }
    int mn = 1e18;
    stack<pair<int, int> > st;
    vector<int> lol;
    for(int i=0; i<k; i++) {
      st.push(pq.top());
      mn = min(mn, pq.top().first);
      lol.push_back(pq.top().second);
      pq.pop();
    }
    int cmp = 0;
    if(pq.size()) cmp = pq.top().first;
    mn = max((mn + 1) / 2, mn - cmp);
    while(st.size()) {
      if(st.top().first != mn) {
        pq.push({st.top().first - mn, st.top().second});
      }
      st.pop();
    }
    for(int x: lol) {
      a[x] -= mn;
    }
    lol.push_back(mn);
    ops.push_back(lol);
  }
  for(int i=1; i<=n; i++) {
    if(a[i] != 0) {
      cout << "-1\n"; return;
    }
  }
  cout << ops.size() << "\n";
  for(vector<int> v: ops) {
    cout << v.back();
    for(int i=0; i<k; i++) cout << " " << v[i];
    cout << "\n";
  }
}
int32_t main() {
  ios::sync_with_stdio(0);
  cin.tie(0);
  int t=1;
  //cin>>t;
  for(int i=1; i<=t; i++)solve(i);
}

Compilation message (stderr)

nicegift.cpp: In function 'void solve(long long int)':
nicegift.cpp:31:18: warning: comparison of integer expressions of different signedness: 'std::priority_queue<std::pair<long long int, long long int> >::size_type' {aka 'long unsigned int'} and 'long long int' [-Wsign-compare]
   31 |     if(pq.size() < k) {
      |        ~~~~~~~~~~^~~

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