Submission #479171

#	Time	Username	Problem	Language	Result	Execution time	Memory
479171		Neos	Zapina (COCI20_zapina)	C++14	110 / 110	400 ms	2116 KiB

zapina

#include <bits/stdc++.h>
 
using namespace std;
 
typedef long long ll;
typedef long double ld;
typedef unsigned long long ull;
typedef pair<ll, ll> ii;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef vector<ii> vii;
typedef vector<vi> vvi;
typedef vector<vll> vvll;
typedef vector<vii> vvii;
 
#define task "test"
#define fastIO ios::sync_with_stdio(false), cin.tie(NULL), cout.tie(NULL)
#define forw(i, l, r) for( ll i = (l) ; i < (r) ; i++ )
#define forb(i, r, l) for( ll i = (r) ; i >= (l) ; i-- )
#define sz(x) (int)x.size()
#define fi first
#define se second
#define all(x) x.begin(), x.end()
#define numBit(x) __builtin_popcount(x)
#define lb lower_bound
#define ub upper_bound
#define ar array
#define endl '\n'
 
const int dx[4] = {-1, 0, 1, 0};
const int dy[4] = {0, -1, 0, 1};
 
const int N = 350 + 7;
const ll inf = 0x3f3f3f3f;
const int MOD = 1e9 + 7;
 
int n, C[N][N], dp[2][N][N];
bool avail[2][N][N];
 
int add(int x, int y) {
  x += y; if (x >= MOD) x -= MOD;
  return x;
}
 
int mul(int x, int y) {
  return 1LL * x * y % MOD;
}
 
int fexp(int x, int y) {
  int ans = 1;
  while (y > 0) {
    if (y & 1) ans = mul(ans, x);
    x = mul(x, x);
    y >>= 1;
  }
  return ans;
}
 
int DP(bool happy, int n, int k) {
  if (n == 0) return happy && (k == 0);
  if (avail[happy][n][k]) return dp[happy][n][k];
  avail[happy][n][k] = 1;
 
  int ans = 0;
  forw(i, 0, k + 1)
    ans = add(ans, mul(C[k][i], DP(happy | (i == n), n - 1, k - i)));
  return dp[happy][n][k] = ans;
}
 
int main() {
  fastIO;
 
  forw(i, 0, N) forw(j, 0, min(1ll * N, i) + 1)
    if (j == 0 || j == i) C[i][j] = 1;
    else C[i][j] = add(C[i - 1][j], C[i - 1][j - 1]);
 
  cin >> n;
  cout << DP(0, n, n) << endl; // happy, indx, remaining task
}

• Subtask 1: 22 / 22
• Subtask 2: 33 / 33
• Subtask 3: 55 / 55