Submission #306474

#	Time	Username	Problem	Language	Result	Execution time	Memory
306474		VROOM_VARUN	Bootfall (IZhO17_bootfall)	C++14	100 / 100	641 ms	4172 KiB

bootfall

/*
ID: varunra2
LANG: C++
TASK: bootfall
*/

#include<bits/stdc++.h>
using namespace std;

#ifdef DEBUG
#include "lib/debug.h"
#define debug(...) cerr << "[" << #__VA_ARGS__ << "]:", debug_out(__VA_ARGS__)
#define debug_arr(...) \
  cerr << "[" << #__VA_ARGS__ << "]:", debug_arr(__VA_ARGS__)
#pragma GCC diagnostic ignored "-Wsign-compare"
//#pragma GCC diagnostic ignored "-Wunused-parameter"
//#pragma GCC diagnostic ignored "-Wunused-variable"
#else
#define debug(...) 42
#endif

#define EPS 1e-9
#define IN(A, B, C) assert(B <= A && A <= C)
#define INF (int)1e9
#define MEM(a, b) memset(a, (b), sizeof(a))
#define MOD 1000000007
#define MP make_pair
#define PB push_back
#define all(cont) cont.begin(), cont.end()
#define rall(cont) cont.end(), cont.begin()
#define x first
#define y second

const double PI = acos(-1.0);
typedef long long ll;
typedef long double ld;
typedef pair<int, int> PII;
typedef map<int, int> MPII;
typedef multiset<int> MSETI;
typedef set<int> SETI;
typedef set<string> SETS;
typedef vector<int> VI;
typedef vector<PII> VII;
typedef vector<VI> VVI;
typedef vector<string> VS;

#define rep(i, a, b) for(int i = a; i < (b); ++i)
#define trav(a, x) for(auto& a : x)
#define sz(x) (int)(x).size()
typedef pair<int, int> pii;
typedef vector<int> vi;
#pragma GCC diagnostic ignored "-Wsign-compare"
// util functions

#define N 502
#define siz N * N + 1

int n;

int main() {
// #ifndef ONLINE_JUDGE
  // freopen("bootfall.in", "r", stdin);
  // freopen("bootfall.out", "w", stdout);
// #endif
  cin.sync_with_stdio(0); cin.tie(0);

  cin >> n;

  VI vals(n);

  for(int i = 0; i < n; i++) {
    cin >> vals[i];
  }

  int sm = accumulate(all(vals), 0);

  VI cur(siz, 0), prv(siz, 0);

  cur[0] = prv[0] = 1;

  for(int i = 0; i < n; i++) {
    for(int j = vals[i]; j < siz; j++) {
      cur[j] += prv[j - vals[i]];
    }
    prv = cur;
  }

  bitset<siz> ret;
  bitset<siz> each;

  if(sm&1 or cur[sm/2] == 0) {
    cout << "0\n";
    return 0;
  }


  VI a;
  ret.set();
  for(int i = 0; i < n; i++) {
    sm -= vals[i];
    a = cur;
    each.reset();
    // undo
    for(int ii = vals[i]; ii < siz; ii++) {
      if(a[ii]) a[ii] -= a[ii - vals[i]]; 
    }
    for(int ii = 0; ii <= sm; ii++) {
      if(a[ii]) {
        int l, r;
        l = ii;
        r = sm - l;
        each[abs(r - l)] = 1;
      }
    }
    ret &= each;
    sm += vals[i];
  }

  cout << ret.count() << '\n';

  for(int i = 0; i < siz; i++) {
    if(ret[i]) cout << i << " ";
  }
  cout << '\n';

  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