Submission #493559

#	Time	Username	Problem	Language	Result	Execution time	Memory
493559		irmuun	Gift (IZhO18_nicegift)	C++17	7 / 100	2005 ms	24736 KiB

nicegift

#include<bits/stdc++.h>
using namespace std;
#define pb push_back
#define ll long long
#define ff first
#define ss second
#define PI 3.14159265359
ll n,m,t,p,h,c,d,e,f,i,j,k,r,l,mod=1000000007,mod1=998244353,MAX=1e18,ans;
pair<ll,ll>a[1000001],b;
string s,u;
ll df[101];
vector<pair<ll,ll> >v;
vector<ll>dv[101];
void dfs(ll x){
    df[x]=1;
    for(ll i=0;i<dv[x].size();i++){
        if(df[dv[x][i]]==0){
            dfs(dv[x][i]);
        }
    }
}
ll fastPow(ll a,ll b){
    ll d=1;
    while(b>0){
        if(b%2==1){
            d=d*a%mod;
        }
        b/=2;
        a=a*a%mod;
    }
    return d;
}
int main(){
    cin>>n>>k;
    ll t=0;
    ll mx=0;
    for(i=1;i<=n;i++){
        cin>>a[i].ff;
        t+=a[i].ff;
        a[i].ss=i;
        mx=max(mx,a[i].ff);
    }
    if(t%k!=0){
        cout<<-1;
        return 0;
    }
    if(k==2){
        if(mx>t-a[n].ff){
            cout<<-1;
            return 0;
        }
        cout<<t/2<<endl;
        sort(a+1,a+n+1);
        while(t>0){
            cout<<1<<' '<<a[n-1].ss<<' '<<a[n].ss<<endl;
            a[n-1].ff--;
            a[n].ff--;
            t-=2;
            sort(a+1,a+n+1);
        }
    }
}

Compilation message (stderr)

nicegift.cpp: In function 'void dfs(long long int)':
nicegift.cpp:16:17: warning: comparison of integer expressions of different signedness: 'long long int' and 'std::vector<long long int>::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   16 |     for(ll i=0;i<dv[x].size();i++){
      |                ~^~~~~~~~~~~~~

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