Submission #393422

#	Time	Username	Problem	Language	Result	Execution time	Memory
393422		SoGood	Bootfall (IZhO17_bootfall)	C++17	100 / 100	535 ms	2916 KiB

bootfall

#pragma GCC optimize ("Ofast")
#pragma GCC optimize ("unroll-loops")
#pragma GCC target("avx,avx2,fma")

#include <bits/stdc++.h>
#include <ext/pb_ds/assoc_container.hpp>
#include <ext/pb_ds/tree_policy.hpp>
#include <ext/rope>
#define pb push_back
#define F first
#define S second
#define ins insert
#define mp make_pair
#define fo(i, n1, n, x) for(int i = n1; i <= n; i += x)
#define foo(i, n, n1, x) for(int i = n; i >= n1; i -= x)
#define bit __builtin_popcount
#define md (l + ((r - l) / 2))
#define all(x) x.begin(),x.end()
#define eb emplace_back
#define ub upper_bound
#define lb lower_bound
#define ios ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0)
#define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)

using namespace std;
//using namespace __gnu_pbds;
//using namespace __gnu_cxx;


using ll = long long;

//#define int ll

using pii = pair<int,int>;
using pll = pair<ll,ll>;
using vi = vector<int>;



const int N = 2e5 + 11, mod = 1e9 + 7, mod2 = 998244353;
const int MAX = 1e5 + 11;
const int INF1 = 2e9 + 11;
const ll INF2 = 6e18 + 11;
const double INF3 = 1e8 + 11;
const int base = 500;
const int P = 31;
const int dx[] = {1, -1, 0, 0, 1, 1, -1, -1};
const int dy[] = {0, 0, 1, -1, 1, -1, 1, -1};
const double EPS = 1e-4;
const double PI = acos(-1.0);


//template<typename T> using ordered_set = tree <T, null_type, less <T>, rb_tree_tag, tree_order_statistics_node_update>;
template<typename T1, typename T2> inline void chmin(T1 &a, T2 b) { if (a > b) a = b; }
template<typename T1, typename T2> inline void chmax(T1 &a, T2 b) { if (a < b) a = b; }


mt19937 rng(chrono::steady_clock::now().time_since_epoch().count());
int rnd(int l, int r) { return uniform_int_distribution<int> (l, r)(rng); }

int n, a[555], pref[555], sum[555], cnt[500005], dp[500005], ans;
main() {
  file("paint");
  ios;
  cin >> n;
  fo(i, 1, n, 1) cin >> a[i], pref[i] = pref[i - 1] + a[i];
  fo(i, 1, n, 1) sum[i] = pref[i - 1] + pref[n] - pref[i];
  dp[0] = 1;
  fo(i, 1, n, 1) {
    foo(j, pref[n], a[i], 1) {
      dp[j] += dp[j - a[i]];
    }
  }
  if (pref[n] % 2 || !dp[pref[n]/2]) return !(cout << 0);
  fo(i, 1, n, 1) {
    fo(j, a[i], pref[n], 1) dp[j] -= dp[j - a[i]];
    fo(j, 0, pref[n], 1) {
      if (dp[j]) {
        int left = sum[i] - j;
        if (left >= j)
        ++cnt[left-j];
        if (cnt[left-j] == n) ++ans;
      }
    }
    foo(j, pref[n], a[i], 1) dp[j] += dp[j - a[i]];
  }
  cout << ans << "\n";
  fo(i, 0, pref[n], 1) if (cnt[i] == n) cout << i << " ";
  return 0;
}
/**
500000
250000

4
1 3 1 5

6
3 5 7 11 9 13

3
2 2 2
*/

Compilation message (stderr)

bootfall.cpp:62:6: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   62 | main() {
      |      ^
bootfall.cpp: In function 'int main()':
bootfall.cpp:23:48: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   23 | #define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
      |                                         ~~~~~~~^~~~~~~~~~~~~~~~~~~~
bootfall.cpp:63:3: note: in expansion of macro 'file'
   63 |   file("paint");
      |   ^~~~
bootfall.cpp:23:77: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
   23 | #define file(s) if (fopen(s".in", "r")) freopen(s".in", "r", stdin), freopen(s".out", "w", stdout)
      |                                                                      ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
bootfall.cpp:63:3: note: in expansion of macro 'file'
   63 |   file("paint");
      |   ^~~~

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