Submission #1125803

#	Time	Username	Problem	Language	Result	Execution time	Memory
1125803		boris_7	Gift (IZhO18_nicegift)	C++20	30 / 100	257 ms	51248 KiB

nicegift

#include<bits/stdc++.h>

using namespace std;
using ll = long long;

void solve() {
    int n,k;
    cin>>n>>k;
    vector<int>v(n);
    int sum = 0;
    multiset<pair<int,int>>ms;
    for(int i=0;i<n;i++){
        cin>>v[i];
        ms.insert({v[i],i});
        sum+=v[i];
    }
    vector<vector<pair<int,int>>>ans;
    if(sum%k) cout<<"-1\n";
    else{
        while(ms.size()>=k){
            vector<pair<int,int>>z;
            for(int i = 0;i<k;i++){
                pair<int,int> a = *ms.rbegin();
                ms.erase(ms.find(a));
                a.first--;
                z.push_back(a);
            }
            ans.push_back(z);
            for(pair<int,int> &i:z){
                if(i.first) ms.insert(i);
            }
        }
        if(ms.size()  && ms.size()<k) cout<<-1<<endl;
        else{
            cout<<ans.size()<<endl;
            for(auto &i:ans){
                cout<<1<<" ";
                for(pair<int,int> &j:i) cout<<j.second+1<<" ";
                cout<<endl;
            }
        }
    }
}

signed main() {
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr);
    // ll t;cin>>t;while(t--)
        solve();
}

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