Submission #1077742

# Submission time Handle Problem Language Result Execution time Memory
1077742 2024-08-27T08:50:51 Z prvocislo Seesaw (JOI22_seesaw) C++17
100 / 100
108 ms 22212 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;
	for (int i = 1; i <= n; i++)
	{
		int l = 0, r = n - i;
		while (l < r)
		{
			int m = (l + r + 1) / 2;
			if (avg(m, m + i - 1) <= w) l = m;
			else r = m - 1;
		}
		v.push_back({ avg(l, l + i - 1), i });
		if (l + i < n) v.push_back({ avg(l + 1, l + i), i });
	}
	ld ans = w;
	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:50:20: 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]
   50 |  for (int l = 0; l < v.size(); l++)
      |                  ~~^~~~~~~~~~
seesaw.cpp:52:23: 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]
   52 |   while (cnt < n && r < v.size())
      |                     ~~^~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 344 KB Output is correct
5 Correct 0 ms 452 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 344 KB Output is correct
5 Correct 0 ms 452 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 1 ms 600 KB Output is correct
9 Correct 1 ms 728 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 1 ms 604 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 344 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 0 ms 344 KB Output is correct
5 Correct 0 ms 452 KB Output is correct
6 Correct 0 ms 348 KB Output is correct
7 Correct 0 ms 348 KB Output is correct
8 Correct 1 ms 600 KB Output is correct
9 Correct 1 ms 728 KB Output is correct
10 Correct 1 ms 604 KB Output is correct
11 Correct 1 ms 604 KB Output is correct
12 Correct 108 ms 21856 KB Output is correct
13 Correct 99 ms 21996 KB Output is correct
14 Correct 97 ms 22212 KB Output is correct
15 Correct 93 ms 21952 KB Output is correct
16 Correct 99 ms 21964 KB Output is correct