Submission #1127007

#	Time	Username	Problem	Language	Result	Execution time	Memory
1127007		gawr_gura	Seesaw (JOI22_seesaw)	C++20	1 / 100	62 ms	328 KiB

seesaw

#include <bits/stdc++.h>

using namespace std;

#define int long long
using ii = pair<int, int>;
using tp = tuple<int, int, int>;

const int N = 2e5 + 5;

int n, a[N];

namespace sub1{
  int pref[N];

  int get(int l, int r){
    return pref[r] - pref[l - 1];
  }

  void solve(){
    for(int i = 1; i <= n; i++) pref[i] = pref[i - 1] + a[i];

    long double res = 1e18;
    for(int msk = 0; msk < (1 << n - 1); msk++){
      int L = 1, R = n;
      long double mx, mn;
      mx = mn = (long double)get(L, R) / n;


      for(int i = 0; i < n - 1; i++){
        if(msk >> i & 1) R -= 1;
        else L += 1;
        mx = max(mx, (long double)get(L, R) / (R - L + 1));
        mn = min(mn, (long double)get(L, R) / (R - L + 1));
      }
      res = min(res, mx - mn);
    }
    cout << setprecision(12) << fixed << res << "\n";
  }
}

int32_t main(){
  cin.tie(0)->sync_with_stdio(0);
  #define task "SEESAW"
  if(fopen(task ".inp", "r")){
    freopen(task ".inp", "r", stdin);
    freopen(task ".out", "w", stdout);
  }
  cin >> n;
  for(int i = 1; i <= n; i++) cin >> a[i];

  sub1::solve();

  return 0;
}
/*
3
1 2 4

6
1 2 5 6 8 9
*/

Compilation message (stderr)

seesaw.cpp: In function 'int32_t main()':
seesaw.cpp:46:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   46 |     freopen(task ".inp", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
seesaw.cpp:47:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   47 |     freopen(task ".out", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 1 / 1
• Subtask 2: 0 / 33
• Subtask 3: 0 / 33
• Subtask 4: 0 / 33