제출 #1128036

#	제출 시각	아이디	문제	언어	결과	실행 시간	메모리
1128036		Vietnow	Bootfall (IZhO17_bootfall)	C++20	0 / 100	2 ms	320 KiB

bootfall

#include <bits/stdc++.h>
#define yes cout<<"YES\n"
#define no cout<<"NO\n"
#define int long long
#define ff first
#define ss second
#define pb push_back
#define y1 zildjian
#define left radio
#define right head
 
using namespace std;
 
const int N = 3e5+10;
const int INF = 1e18;
const int mod = 1e9+7;
const int mod1 = 998244353;
mt19937_64 rng(chrono::steady_clock::now().time_since_epoch().count());

int n;
int a[N];
int dp[N];

void solve(){
    cin>>n;
    int sum = 0;
    for(int i = 1;i<=n;i++){
        cin>>a[i];
        sum+=a[i];
    }
    if(sum%2){
        cout<<0;
        return;
    }
    for(int i = 2;i<=n;i++){
        if(a[i]%2 != a[i-1]%2){
            cout<<'0';
            return;
        }
    }
    dp[0] = 1;
    for(int i = 1;i<=n;i++){
        for(int w = sum;w>=1;w--){
            dp[w] += dp[w-a[i]];
        }
    }
    if(!dp[sum/2]){
        cout<<0<<'\n';
        return;
    }
    vector<int> v;
    for(int i = 1;i<=sum;i++){
        // cout<<dp[i]<<' ';
        if(i%2 == a[1]%2){
            v.pb(i);
        }
    }
    vector<int> ans;
    for(auto x:v){
        bool ok = 1;
        // cout<<x<<'\n';
        for(int i = 1;i<=n;i++){
            for(int w = 0;w+a[i]<=sum;w++){
                if(dp[w] && dp[w+a[i]]){
                    dp[w+a[i]] -= dp[w];
                }
            }
            // cout<<i<<":\n";
            for(int w = sum;w>=x;w--){
                dp[w] += dp[w-x];
            }
            // for(int w = 1;w<=sum/2;w++){
            //     cout<<dp[w]<<' ';
            // }
            // cout<<'\n';
            if((sum-a[i]+x)%2 || !dp[(sum-a[i]+x)/2]){
                ok = 0;
                for(int w = 0;w+x<=sum;w++){
                    if(dp[w] && dp[w+x]){
                        dp[w+x] -= dp[w];
                    }
                }
                for(int w = sum;w>=a[i];w--){
                    dp[w] += dp[w-a[i]];
                }
                break;
            }
            for(int w = 0;w+x<=sum;w++){
                if(dp[w] && dp[w+x]){
                    dp[w+x] -= dp[w];
                }
            }
            for(int w = sum;w>=a[i];w--){
                dp[w] += dp[w-a[i]];
            }
            // for(int w = 1;w<=sum/2;w++){
            //     cout<<dp[w]<<' ';
            // }
            // cout<<'\n';
        }
        if(ok){
            ans.pb(x);
        }
    }
    // cout<<'\n';
    cout<<ans.size()<<'\n';
    for(auto x:ans) cout<<x<<' ';

}

signed main(){
    freopen("bootfall.in","r",stdin); 
    freopen("bootfall.out","w",stdout);
    ios_base::sync_with_stdio(0);
    cin.tie(nullptr);
    // cout.tie(nullptr);
    int t = 1;
    // cin>>t;
    for(int i = 1;i<=t;i++){
        // cout<<"Case "<<i<<": ";
        solve();
    }
}

컴파일 시 표준 에러 (stderr) 메시지

bootfall.cpp: In function 'int main()':
bootfall.cpp:112:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  112 |     freopen("bootfall.in","r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:113:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  113 |     freopen("bootfall.out","w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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