Submission #673419

#	Time	Username	Problem	Language	Result	Execution time	Memory
673419		pragmatist	Bootfall (IZhO17_bootfall)	C++17	0 / 100	5 ms	212 KiB

bootfall

/*
#pragma comment(linker, "/stack:200000000")
#pragma GCC optimize("O3")
#pragma GCC target ("avx2")
#pragma GCC optimize("Ofast")
#pragma GCC target("sse,sse2,sse3,ssse3,sse4,popcnt,abm,mmx,avx,tune=native")
#pragma GCC optimize("unroll-loops")
*/

#pragma GCC target("avx2", "bmi", "bmi2", "lzcnt", "popcnt")

#include<bits/stdc++.h>
 
#define sz(v) (int)v.size()
#define ll long long
#define pb push_back
#define x first
#define y second
#define all(v) v.begin(), v.end()
#define rall(v) v.rbegin(), v.rend()
#define nl "\n"

using namespace std;
using pii = pair<int, int>;

const int N = (int)5e2 + 7; // make sure this is right
const int M = 1000;
const int inf = (int)1e9;
const ll INF = (ll)3e18 + 7; 
const ll MOD = (ll)998244353; // make sure this is right

pii dir[] = {{1, 0}, {0, 1}, {-1, 0}, {0, -1}};

int n, a[N], dp[M];
bool ans[N];

int sum(int x, int y) {
	x += y;
	if(x >= MOD) x -= MOD;
	return x;
}

int sub(int x, int y) {
	x -= y;
	if(x < 0) x += MOD;
	return x;
}

void add(int x) {
	for(int i = M - 1; i >= x; --i) {
		dp[i] = sum(dp[i], dp[i - x]);
	}
}

void del(int x) {
	for(int i = x; i < M; ++i) {
		dp[i] = sub(dp[i], dp[i - x]);
	}
}

void solve() {
	cin >> n;
	dp[0] = 1;
	int sum = 0;
	for(int i = 1; i <= n; ++i) {
		cin >> a[i];
	    add(a[i]);
		sum += a[i];
	}
	n++;        
	vector<int> ans;
	for(int x = 1; x < M; ++x) {
		a[n] = x;
		add(x); 
		bool ok = 1;
		for(int i = 1; i <= n && ok; ++i) {
			del(a[i]);

			int need = (sum + x - a[i]) >> 1;
			if((sum + x - a[i]) & 1) {
				ok = 0;
			} else {                
				ok &= (dp[need]);				
			}
			add(a[i]);			
		}
		if(ok) ans.pb(x);
		del(x);
	}
	
	cout << sz(ans) << nl;
	for(auto x : ans) cout << x << ' ';
}

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

	int test = 1;
	//cin >> test;
	for(int i = 1; i <= test; ++i) {
	 	//cout << "Case #" << i << ": ";
		solve();
	}
	return 0;
}

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