Submission #5541757

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Source Code Expand

#include <iostream>
#include <cstdio>
#include <fstream>
#include <algorithm>
#include <string>
#include <map>
#include <set>
#include <queue>
#include <stack>
#include <vector>
#include <limits.h>
#include <math.h>
#include <functional>
#include <bitset>
#include <iomanip>
#include <cassert>
#include <float.h>
#include <random>

#define repeat(i,n) for (int i = 0; (i) < (n); ++ (i))
#define debug(x) cerr << #x << ": " << x << '\n'
#define debugArray(x,n) for(long long hoge = 0; (hoge) < (n); ++ (hoge)) cerr << #x << "[" << hoge << "]: " << x[hoge] << '\n'
#define debugArrayP(x,n) for(long long hoge = 0; (hoge) < (n); ++ (hoge)) cerr << #x << "[" << hoge << "]: " << x[hoge].first<< " " << x[hoge].second << '\n'

using namespace std;

typedef long long ll;
typedef unsigned long long ull;
typedef pair<int,int> Pii;
typedef vector<int> vint;
typedef vector<ll> vll;
const ll INF = LLONG_MAX/10;
const ll MOD = 1e9+7;

int N;
double dp[1<<16][20];

int main(){
  cin.tie(0);
  ios::sync_with_stdio(false);
  cin>>N;
  int s=0;
  repeat(i,N){
    int x;cin>>x;
    s |= 1<<x;
  }
  for(int b=1;b<(1<<16);b++){
    for(int x=1;x<15;x++){
      double tmp=0;
      int cnt=0;
      repeat(i,3){
        if((b>>(x-1+i))&1){
          double a =dp[b^(1<<(x-1+i))][1];
          for(int y=2;y<15;y++){
            a = min(a,dp[b^(1<<(x-1+i))][y]);
          }
          tmp += a;
        }else{
          cnt++;
        }
      }
      if(cnt==3)dp[b][x] = INF;
      else dp[b][x] = (tmp+3)/(3-cnt);
    }
  }
  double ans = dp[s][1];
  for(int x=2;x<15;x++){
    ans = min(ans,dp[s][x]);
  }
  printf("%.7lf\n",ans);
  return 0;
}

Submission Info

Judge Result