oj.uz

Submission #1079081

# Submission time Handle Problem Language Result Execution time Memory
1079081 2024-08-28T10:29:48 Z prvocislo Seesaw (JOI22_seesaw) C++17
100 / 100
 108 ms 30696 KB 
// I was grinning like I'm winning, I was hitting my marks
// 'Cause I can do it with a broken heart 
// 1 2 3 4 ...
 
#include <iostream>
#include <iomanip>
#include <vector>
#include <algorithm>
#include <queue>
#include <map>
#include <set>
#include <bitset>
typedef long long ll;
typedef long double ld;
using namespace std;
 
vector<ll> a, pf;
 
ld avg(int l, int r) { return (ld)(pf[r + 1] - pf[l]) / (ld)(r - l + 1); }
 
void chmax(ld& a, ld b) { a = max(a, b); }
void chmin(ld& a, ld b) { a = min(a, b); }
 
int main()
{
	ios::sync_with_stdio(false);
	cin.tie(0);
	int n;
	cin >> n;
	a.assign(n, 0), pf.assign(n + 1, 0);
	for (int i = 0; i < n; i++) cin >> a[i], pf[i + 1] = pf[i] + a[i];
	ld w = avg(0, n - 1);
	vector<pair<ld, int>> v;
	v.push_back({ avg(0, n - 1), n });
	v.push_back({ avg(0, n - 2), n - 1 });
	v.push_back({ avg(1, n - 1), n - 1 });
	int l = 0;
	for (int i = n - 2; i >= 1; i--)
	{
		if (avg(l + 1, l + i) <= w) l++;
		v.push_back({ avg(l, l + i - 1), i });
		v.push_back({ avg(l + 1, l + i), i });
	}
	ld ans = w;
	stable_sort(v.begin(), v.end());
	vector<int> f(n + 1, 0);
	int cnt = 0, r = 0;
	for (int l = 0; l < v.size(); l++)
	{
		while (cnt < n && r < v.size())
		{
			if (!f[v[r].second]) cnt++;
			f[v[r].second]++;
			r++;
		}
		if (cnt == n) ans = min(ans, v[r - 1].first - v[l].first);
		f[v[l].second]--;
		if (!f[v[l].second]) cnt--;
	}
	cout << setprecision(9) << fixed;
	cout << ans << "\n";
	return 0;
}

Compilation message

seesaw.cpp: In function 'int main()':
seesaw.cpp:48:20: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long double, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   48 |  for (int l = 0; l < v.size(); l++)
      |                  ~~^~~~~~~~~~
seesaw.cpp:50:23: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<std::pair<long double, int> >::size_type' {aka 'long unsigned int'} [-Wsign-compare]
   50 |   while (cnt < n && r < v.size())
      |                     ~~^~~~~~~~~~

Subtask #1
1.0 / 1.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 0 ms 348 KB Output is correct

Subtask #2
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 344 KB Output is correct
5 Correct 0 ms 376 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct

Subtask #3
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 344 KB Output is correct
5 Correct 0 ms 376 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 724 KB Output is correct
10 Correct 1 ms 600 KB Output is correct
11 Correct 1 ms 604 KB Output is correct

Subtask #4
33.0 / 33.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 1 ms 600 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 344 KB Output is correct
5 Correct 0 ms 376 KB Output is correct
6 Correct 1 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 1 ms 604 KB Output is correct
9 Correct 1 ms 724 KB Output is correct
10 Correct 1 ms 600 KB Output is correct
11 Correct 1 ms 604 KB Output is correct
12 Correct 93 ms 30660 KB Output is correct
13 Correct 100 ms 30512 KB Output is correct
14 Correct 108 ms 30652 KB Output is correct
15 Correct 99 ms 30612 KB Output is correct
16 Correct 91 ms 30696 KB Output is correct