Submission #672417

#	Time	Username	Problem	Language	Result	Execution time	Memory
672417		Baytoro	Bootfall (IZhO17_bootfall)	C++17	100 / 100	600 ms	4328 KiB

bootfall

#include <bits/stdc++.h>
using namespace std;
#define ios ios::sync_with_stdio(false); cin.tie(NULL);
#define pb push_back
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define fr first
#define sc second
#define int long long
//#define endl '\n'
void fopn(string name){
	freopen((name+".in").c_str(),"r",stdin);
	freopen((name+".out").c_str(),"w",stdout);
}
const int INF=1e18,mod=998244353;
const int N=3e5;
int dp[N+5];
int sum=0;
void add(int x){
	for(int i=N;i>=x;i--){
		dp[i]+=dp[i-x];
	}
}
void remove(int x){
	for(int i=x;i<=N;i++){
		dp[i]-=dp[i-x];
	}
}
int n;
void solve(){
	int n;
	cin>>n;
	vector<int> vec(n);
	dp[0]=1;
	for(int i=0;i<n;i++){
		cin>>vec[i];
		sum+=vec[i];
		add(vec[i]);
	}
	if(sum%2 || !dp[sum/2]){
		cout<<0<<endl;
		return;
	}
	vector<bool> used(N+5,1);
	for(int i=0;i<n;i++){
		remove(vec[i]);
		for(int j=1;j<=N;j++){
			if(!used[j]) continue;
			if((sum-vec[i]+j)%2 || !dp[(sum-vec[i]+j)/2]){
				used[j]=0;
			}
		}
		add(vec[i]);
	}
	vector<int> ans;
	for(int i=1;i<=N;i++){
		if(used[i]) ans.pb(i);
	}
	cout<<ans.size()<<endl;
	for(auto it: ans)
		cout<<it<<' ';
}
main(){
	//ios;
	int T=1;
	//cin>>T;
	while(T--){
		solve();
	}
}

Compilation message (stderr)

bootfall.cpp:63:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   63 | main(){
      | ^~~~
bootfall.cpp: In function 'void fopn(std::string)':
bootfall.cpp:12:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |  freopen((name+".in").c_str(),"r",stdin);
      |  ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:13:9: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |  freopen((name+".out").c_str(),"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