Submission #604388

#	Time	Username	Problem	Language	Result	Execution time	Memory
604388		Aleee	Kangaroo (CEOI16_kangaroo)	C++14	6 / 100	2083 ms	126372 KiB

kangaroo

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

#define pb push_back
#define all(a) (a).begin(), (a).end()
#define endl '\n'
#define forn(i, l, n) for (int i = l; i < int(n); i++)

typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vll;
typedef pair<int, int> pii;

const int INF = 1e9 + 7;
vll dp(2000, -1);
vll cant(2001, 0);
int n, cs, cf;

vector<string> ans;

void solve(int prev, int act, vector<bool> disp, int aux, string path)
{
  if (aux == n)
  {
    if (act == cf)
      ans.pb(path);
    return;
  }
  // cout << prev << " -> " << act << " " << aux << endl;
  if (prev < act)
  {
    forn(i, 1, act)
    {
      if (!disp[i] || aux == n - 1)
      {
        cant[i]++;
        disp[i] = 1;
        aux++;
        solve(act, i, disp, aux, path + "->" + to_string(i));
        disp[i] = 0;
        aux--;
      }
    }
  }
  else if (prev > act)
  {
    forn(i, act + 1, n + 1)
    {
      if (!disp[i] || aux == n - 1)
      {
        cant[i]++;
        disp[i] = 1;
        aux++;
        solve(act, i, disp, aux, path + "->" + to_string(i));
        disp[i] = 0;
        aux--;
      }
    }
  }
  else
  {
    forn(i, 1, n + 1)
    {
      if (!disp[i] || aux == n - 1)
      {
        cant[i]++;
        disp[i] = 1;
        aux++;
        solve(act, i, disp, aux, path + "->" + to_string(i));
        disp[i] = 0;
        aux--;
      }
    }
  }
  return;
}

int main() // Ale C.
{
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);
  // freopen("output.txt", "w", stdout);
  cin >> n >> cs >> cf;
  vector<bool> disp(2000, 0);
  disp[cs] = disp[cf] = 1;
  solve(cs, cs, disp, 1, to_string(cs));
  cout << cant[cf] << endl;
  /*  sort(all(ans));
   forn(i, 0, ans.size()) cout << ans[i] << endl; */
  return 0;
}

• Subtask 1: 6 / 6
• Subtask 2: 0 / 30
• Subtask 3: 0 / 15
• Subtask 4: 0 / 49