Submission #555339

#	Time	Username	Problem	Language	Result	Execution time	Memory
555339		ngpin04	Bootfall (IZhO17_bootfall)	C++14	100 / 100	115 ms	3528 KiB

bootfall

#include <bits/stdc++.h>
#define fi first
#define se second
#define mp make_pair
#define TASK ""
#define ALL(x) (x).begin(), (x).end() 
using namespace std;
template <typename T1, typename T2> bool mini(T1 &a, T2 b) {
	if (a > b) {a = b; return true;} return false;
}
template <typename T1, typename T2> bool maxi(T1 &a, T2 b) {
	if (a < b) {a = b; return true;} return false;
}
const int N = 25e4 + 5;
const int oo = 1e9;
const long long ooo = 1e18;
const int mod = 1e9 + 7; // 998244353;
const long double pi = acos(-1);

bitset <N> dp;

int a[N];
int n, tot;

int cnt[2 * N];

void solve(int l, int r, bitset <N> &dp) {
	if (l == r) {
		for (int i = 0; i <= (tot >> 1); i++) {
			int x = i;
			int y = tot - i - a[l];
			if (x <= y)
				cnt[y - x] += dp[i];
		}

		// cerr << "left " << l << "\n";
		// for (int i = 0; i <= (tot >> 1); i++)
		// 	if (dp[i])
		// 		cerr << i << " ";
		// cerr << "\n";
		return;
	}

	int mid = (l + r) >> 1;
	
	bitset <N> tmp = dp;
	for (int i = l; i <= mid; i++)
		tmp |= (tmp << a[i]);
	
	solve(mid + 1, r, tmp);

	for (int i = mid + 1; i <= r; i++)
		dp |= (dp << a[i]);
	solve(l, mid, dp);
}

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	#ifdef ONLINE_JUDGE
	// freopen(TASK".inp","r",stdin);
	// freopen(TASK".out","w",stdout);
	#endif
	cin >> n;
	for (int i = 1; i <= n; i++)
		cin >> a[i];

	tot = accumulate(a + 1, a + n + 1, 0);
	dp[0] = true;
	for (int i = 1; i <= n; i++)
		dp |= (dp << a[i]);

	if ((tot & 1) || !dp[tot >> 1])
		return cout << 0, 0;

	dp.reset();
	dp[0] = 1;

	solve(1, n, dp);

	vector <int> res;
	for (int i = 1; i <= tot; i++)
		if (cnt[i] == n)
			res.push_back(i);

	cout << res.size() << "\n";
	for (int x : res)
		cout << x << " ";
	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