Submission #670349

#	Time	Username	Problem	Language	Result	Execution time	Memory
670349		mychecksedad	Bootfall (IZhO17_bootfall)	C++17	100 / 100	646 ms	5764 KiB

bootfall

/* Author : Mychecksdead */
#include<bits/stdc++.h>
using namespace std;
#define pb push_back
const int N = 510, M = 510, MX = 520*520;

int n, a[N], S = 0;
bitset<MX/2> dp[N];
void solve(){
	cin >> n;
	bool ok = 1;
	for(int i = 1; i <= n; ++i){
		cin >> a[i];
		S += a[i];
		if(a[i] % 2 != a[1] % 2){
			ok = 0;
		}
	}

	if(!ok || S % 2){
		cout << 0;
		return;
	}

	vector<int> used(M);

	vector<int> s;
	s.pb(0);
	for(int i = 1; i <= n; ++i){
		if(!used[a[i]]) s.pb(i);
		used[a[i]] = 1;
	}

	for(int i: s){
		dp[i][0] = 1;
		for(int l = 1; l <= n; ++l){
			if(i == l) continue;
			dp[i] = dp[i] | (dp[i] << a[l]);
		}
	}

	vector<int> possible;

	for(int x = 2 - (a[1] % 2); x <= S; x += 2){	
		ok = 1;
		a[0] = x;
		for(int i: s){
			bool state1 = 0, state2 = 0;
			int req = -1, req1 = -1;			

			int c = S + x - a[i];

			req = c >> 1;

			if(req > S/2) req = c - req;

			if(req <= S/2)
				state1 = dp[i][req];
			
			if(i > 0){

				req1 = (c >> 1) - x;

				if(req1 >= 0){

					if(req1 > S/2) req1 = c - req1;

					if(req1 <= S/2)
						state2 = dp[i][req1];
				}
			}

			if(!(state1 | state2)){
				ok = 0;
				break;
			}
		}
		if(ok){
			possible.pb(x);
		}
	}

	cout << possible.size() << '\n';
	for(int p: possible) cout << p << ' ';
}




int main(){
    cin.tie(0); ios::sync_with_stdio(0);
    solve();
    return 0;
 
}

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