Submission #168496

#	Time	Username	Problem	Language	Result	Execution time	Memory
168496		achibasadzishvili	Gift (IZhO18_nicegift)	C++14	49 / 100	2083 ms	103148 KiB

nicegift

#include <bits/stdc++.h>
#define ll long long
#define f first
#define s second
#define pb push_back
#define mp make_pair
using namespace std;
ll n,k,a[2000005],s,las,p,cur,maxi,l,r,mid,can;
set<pair<ll,ll> >st;
vector<vector<ll> >ans;
vector<ll>g;
int main(){
    ios::sync_with_stdio(0);
  cin>>n>>k;
  bool ok = 1;
    for(int i=1; i<=n; i++){
        cin>>a[i];
       if(a[i] != a[1])ok = 0;
        s += a[i];
        st.insert(mp(-a[i] , i));
    }
 
    if(s % k){
        cout << "-1";
        return 0;
    }
 
    ll raod = s / k;
    ll sum = s;
    ll ra = 0;
    while(sum){
    	if(ra > 2000000){
    		cout << "-1";
    		return 0;
    	}
        if((int)st.size() < k){
            cout << "-1";
            return 0;
        }
        p = 0,cur = 0;
        g.clear();
        maxi = -(*st.begin()).f;
        for(set<pair<ll,ll> >::iterator it = st.begin(); it != st.end(); it++){
            p++;
            if(p > k){
                cur = (*it).s;
                break;
            }
            las = (*it).s;
        }
        l = 1 , r = a[las] , mid , can = -1;
        while(r >= l){
            mid = (l + r) / 2;
            if(max(maxi - mid , a[cur]) * k <= sum - mid * k){
                l = mid + 1;
                can = mid;
            }
            else {
                r = mid - 1;
            }
        }
        if(can <= 0){
        	cout << "-1";
        	return 0;
        }
        sum -= can * k;
        ra += k;
        p = 0;
        g.pb(can);
        for(set<pair<ll,ll> >::iterator it = st.begin(); it != st.end(); it++){
            p++;
            if(p > k){
                cur = (*it).s;
                break;
            }
            g.pb((*it).s);
        }
        for(int i=1; i<g.size(); i++){
            st.erase(mp(-a[g[i]] , g[i]));
            a[g[i]]-=can;
            if(a[g[i]])st.insert(mp(-a[g[i]] , g[i]));
        }
        ans.pb(g);
    }

    cout<<ans.size()<<"\n";
 
    for(int i=0; i<ans.size(); i++)
        for(int j=0; j<ans[i].size(); j++)
        	cout<<ans[i][j]<<" ";
 
 
    return 0;
}

Compilation message (stderr)

nicegift.cpp: In function 'int main()':
nicegift.cpp:51:43: warning: right operand of comma operator has no effect [-Wunused-value]
         l = 1 , r = a[las] , mid , can = -1;
                                           ^
nicegift.cpp:78:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int i=1; i<g.size(); i++){
                      ~^~~~~~~~~
nicegift.cpp:88:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for(int i=0; i<ans.size(); i++)
                  ~^~~~~~~~~~~
nicegift.cpp:89:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
         for(int j=0; j<ans[i].size(); j++)
                      ~^~~~~~~~~~~~~~
nicegift.cpp:15:8: warning: variable 'ok' set but not used [-Wunused-but-set-variable]
   bool ok = 1;
        ^~
nicegift.cpp:28:8: warning: unused variable 'raod' [-Wunused-variable]
     ll raod = s / k;
        ^~~~

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