Submission #1128249

#	Time	Username	Problem	Language	Result	Execution time	Memory
1128249		_Temirhan	Bootfall (IZhO17_bootfall)	C++20	100 / 100	773 ms	4084 KiB

bootfall

#include <bits/stdc++.h>

using namespace std;
  
#define int long long
#define pb push_back
#define sz(x) x.size()
#define F first
#define S second
#define nl '\n'

void Tima() 
{
    #ifndef ONLINE_JUDGE
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
    #endif
}  

const int N = 500 * 500 + 1;
const int inf = 1e12;
const int mod = 1e9 + 7;

signed main() 
{
    // Tima();
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    int n;
    cin >>n;
    int a[n + 1], sum = 0;
    for( int i = 1; i <= n; ++i )
    {
        cin >>a[i];
        sum += a[i];
    }
    vector< int >dp(N, 0);
    dp[0] = 1;
    for( int i = 1; i <= n; ++i )
        for( int w = N - 1; w >= a[i]; --w )
            dp[w] = (dp[w] + dp[w - a[i]]) % mod;
    if( (sum & 1) || !dp[sum / 2] )
    {
        cout <<0;
        return 0;
    }
    vector< bool >ch(N, 1);
    for( int i = 1; i <= n; ++i )
    {
        for( int w = a[i]; w < N; ++w )
            dp[w] = (dp[w] - dp[w - a[i]] + mod) % mod;
        for( int s = 1; s < N; ++s )
            if( (sum - a[i] + s) % 2 == 1 || !dp[(sum - a[i] + s) / 2] )
                ch[s] = false;
        for( int w = N - 1; w >= a[i]; --w )
            dp[w] = (dp[w] + dp[w - a[i]]) % mod;
    }
    vector< int >ans;
    for( int i = 1; i < N; ++i )
        if( ch[i] )
            ans.pb( i );
    cout <<sz(ans) <<nl;
    for( int i: ans )
        cout <<i <<' ';
}

Compilation message (stderr)

bootfall.cpp: In function 'void Tima()':
bootfall.cpp:15:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |     freopen("input.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:16:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   16 |     freopen("output.txt", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

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