Submission #170130

#	Time	Username	Problem	Language	Result	Execution time	Memory
170130		nvmdava	Bootfall (IZhO17_bootfall)	C++17	100 / 100	484 ms	8696 KiB

bootfall

#include <bits/stdc++.h>
using namespace std;
#define ll long long
#define ff first
#define ss second
mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
#define INF 0x3f3f3f3f
#define MOD 1000000007
#define N 1000005

bitset<501> in[250001];
bitset<250001> can;

int a[505];
int cnt[505];

int ans[250005];

vector<int> v;

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

    int n, s = 0;
    cin>>n;
    for(int i = 1; i <= n; ++i){
        cin>>a[i];
        cnt[a[i]]++;
        s += a[i];
    }

    can[0] = 1;

    for(int i = 1; i <= 500; ++i){
        for(int j = 1; j < cnt[i]; ++j){
            can |= can << i;
        }
    }

    for(int i = 1; i <= 500; ++i){
        if(!cnt[i]) continue;
        for(int j = s - i; j >= 0; --j){
            if(can[j]){
                bitset<501> t = in[j];
                t[i] = 1;
                if(!can[j + i]){
                    in[j + i] = t;
                    can[j + i] = 1;
                } else {
                    if(in[j + i].none())
                        continue;
                    in[j + i] &= t;
                }
            }
        }
    }
    if((s & 1) || !can[s / 2]){
        cout<<0;
        return 0;
    }

    for(int i = 1; i <= 500; ++i){
        if(cnt[i]){
            for(int j = 1; j <= s; ++j){
                if(can[j] && in[j][i] == 0){
                    int q = j * 2 + i - s;
                    if(q <= 0) continue;
                    ans[q] += cnt[i];
                }
            }
        }
    }

    for(int i = 1; i <= 250000; i++){
        if(ans[i] == n){
            v.push_back(i);
        }
    }
    cout<<v.size()<<'\n';
    for(auto& x : v)
        cout<<x<<' ';
}

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