Submission #173209

#	Time	Username	Problem	Language	Result	Execution time	Memory
173209		DeD_TihoN	Bootfall (IZhO17_bootfall)	C++14	65 / 100	1080 ms	6928 KiB

bootfall

#pragma GCC optimize ("O3")
#include<bits/stdc++.h>
#include<ext/pb_ds/assoc_container.hpp>
#include<ext/pb_ds/tree_policy.hpp>
#define ff first
#define ss second
#define pb push_back
#define mp make_pair
#define ll long long
#define ld long double
#define all(a) a.begin(),a.end()
#define ull unsigned long long
#define endl '\n'
#define y1 yaumru
#define ios ios_base::sync_with_stdio(false);cin.tie(0);cout.tie(0);
#define iter vector<int>::iterator
using namespace std;
using namespace __gnu_pbds;

template<class T>
using ordered_set=tree<T,null_type,less<T>,rb_tree_tag,tree_order_statistics_node_update>;

template<class T>
using ordered_multiset=tree<T,null_type,less_equal<T>,rb_tree_tag,tree_order_statistics_node_update>;

mt19937 rnd(chrono::steady_clock::now().time_since_epoch().count());
mt19937_64 rnd1(chrono::steady_clock::now().time_since_epoch().count());

//find_by_order
//order_of_key

const int N=500+1;
const int inf=1e9+1e9;
const int mod=1e9+7;
const ld eps=1e-9;
const int M=250000+1;

bitset<M>dp[N];
int a[N];
bool used[N];

main ()
{
    ios;
    int n;
    cin>>n;
    for (int i=1;i<=n;++i){
        cin>>a[i];
    }
    int sum=0;
    bool c1=false;
    bool c2=false;
    for (int i=1;i<=n;++i){
        sum+=a[i];
        if (a[i]%2==1){
            c1=true;
        }
        else {
            c2=true;
        }
    }
    if (c1 && c2){
        cout<<0<<endl;
        exit(0);
    }
    if (sum%2==1){
        cout<<0<<endl;
        exit(0);
    }
    for (int i=0;i<=n;++i){
        if (i==0){
            dp[i][0]=1;
            for (int j=1;j<=n;++j){
                if (j==i)continue;
                bitset<M>f=(dp[i]<<a[j]);
                dp[i]=(dp[i]|f);
            }
            if (dp[0][sum/2]==0){
                cout<<0<<endl;
                exit(0);
            }
        }
        else {
            if (!used[a[i]]){
                used[a[i]]=true;
                dp[a[i]][0]=1;
                for (int j=1;j<=n;++j){
                    if (j==i)continue;
                    bitset<M>f=(dp[a[i]]<<a[j]);
                    dp[a[i]]=(dp[a[i]]|f);
                }
            }
        }
    }
    vector<int>ans;
    for (int i=1;i<=M;++i){
        bool cc=true;
        for (int j=1;j<=n;++j){
            if ((sum-a[j]+i)%2==1){
                cc=false;
                break;
            }
            if ((sum-a[j]+i)%2==0){
                if (dp[a[j]][(sum-a[j]+i)/2]==0){
                    cc=false;
                    break;
                }
            }
        }
        if (cc)ans.pb(i);
    }
    cout<<(int)ans.size()<<endl;
    for (int i=0;i<ans.size();++i){
        cout<<ans[i]<<' ';
    }
}

Compilation message (stderr)

bootfall.cpp:42:7: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
 main ()
       ^
bootfall.cpp: In function 'int main()':
bootfall.cpp:113:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     for (int i=0;i<ans.size();++i){
                  ~^~~~~~~~~~~

• Subtask 1: 6 / 6
• Subtask 2: 7 / 7
• Subtask 3: 15 / 15
• Subtask 4: 16 / 16
• Subtask 5: 21 / 21
• Subtask 6: 0 / 35