Submission #1126520

#	Time	Username	Problem	Language	Result	Execution time	Memory
1126520		wjankowski	Fibonacci representations (CEOI18_fib)	C++20	0 / 100	1 ms	324 KiB

fib

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

constexpr int mod = 1e9+7;

set <int> s;
void add(int a)
{
  if(a == -1) return;
  if(a == 0) a++;
  if(s.count(a+1)) s.erase(a+1), add(a+2);
  else if(s.count(a-1)) s.erase(a-1), add(a+1);
  else if(s.count(a)) s.erase(a), add(a-2), add(a+1);
  else s.insert(a);
}

int main()
{
  ios_base::sync_with_stdio(0);
  cin.tie(0); cout.tie(0);

  int n,dp[2]; cin >> n;
  for(int i=1,a; i<=n; i++)
  {
    cin >> a; add(a);
    int ls = 0;
    for(auto x : s)
    {
      if(!ls) dp[0] = 1, dp[1] = (x-1)/2;
      else
      {
        int v0 = (dp[0]+dp[1])%mod;
        int v1 = ((dp[0]*(x-ls-1)/2)%mod+(dp[1]*(x-ls)/2)%mod)%mod;
        dp[0] = v0, dp[1] = v1;
      }
      ls = x;
    }
    cout << (dp[0]+dp[1])%mod << '\n';
  }
}

• Subtask 1: 0 / 5
• Subtask 2: 0 / 20
• Subtask 3: 0 / 15
• Subtask 4: 0 / 10
• Subtask 5: 0 / 15
• Subtask 6: 0 / 35