oj.uz

Submission #877983

# Submission time Handle Problem Language Result Execution time Memory
877983 2023-11-24T01:18:39 Z loncacbuoidai Sure Bet (CEOI17_sure) C++14
20 / 100
 1 ms 472 KB 
#include <bits/stdc++.h>
using namespace std;

const int N = 1e5 + 5;

int n, k;
float a[N], b[N];

bool check(float f) {
	// cerr << fixed << setprecision(10) << f << '\n';

	int x = ([&] () -> int {
		int l = 1, r = n, ans = n * 3;
		while (l <= r) {
			int mid = (l + r) / 2;
			if ((double)a[mid] - k >= f) {
				ans = mid;
				r = mid - 1;
			} else l = mid + 1;
		}
		return ans;
	}());
	int y = ([&] () -> int {
		int l = 1, r = n, ans = n * 3;
		while (l <= r) {
			int mid = (l + r) / 2;
			if ((double)b[mid] - k >= f) {
				ans = mid;
				r = mid - 1;
			} else l = mid + 1;
		}
		return ans;
	}());
	// cerr << x << ' ' << y << " ok " << (x + y <= k) << '\n';
	return x + y <= k;
}

int32_t main() {
	cin.tie(0)->sync_with_stdio(0);
	if (fopen("OXBET.inp", "r"))
		freopen("OXBET.inp", "r", stdin),
		freopen("OXBET.out", "w", stdout);
	
	cin >> n;
	for (int i = 1; i <= n; i++)
		cin >> a[i] >> b[i];
	
	sort(a + 1, a + n + 1, greater<float>());
	sort(b + 1, b + n + 1, greater<float>());
	for (int i = 1; i <= n; i++)
		a[i] += a[i - 1], b[i] += b[i - 1];
	
	// for (int i = 1; i <= n; i++)
		// cerr << a[i] << ' ' << b[i] << '\n';
	
	// k = 3;
	// check(0.5) << '\n';
	// return 0;
	
	float res = 0;
	for (k = 1; k <= n * 2; k++) {
		// cerr << "k  = " << k << '\n';
		float l = 0, r = 2e8, ans = 0;
		for (int t = 1; t <= 50; t++) {
			float mid = (l + r) / 2;
			if (check(mid)) {
				ans = mid;
				l = mid;
			} else r = mid;
		}
		
		res = max(res, ans);
	}
	
	cout << fixed << setprecision(4) << res;
	
	return 0;
}

Compilation message

sure.cpp: In function 'int32_t main()':
sure.cpp:41:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   41 |   freopen("OXBET.inp", "r", stdin),
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
sure.cpp:42:10: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   42 |   freopen("OXBET.out", "w", stdout);
      |   ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
20.0 / 20.0

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

Subtask #2
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 344 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 472 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Incorrect 1 ms 348 KB Output isn't correct
12 Halted 0 ms 0 KB -

Subtask #3
0 / 40.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 348 KB Output is correct
2 Correct 0 ms 348 KB Output is correct
3 Correct 0 ms 348 KB Output is correct
4 Correct 1 ms 348 KB Output is correct
5 Correct 0 ms 348 KB Output is correct
6 Correct 0 ms 344 KB Output is correct
7 Correct 1 ms 348 KB Output is correct
8 Correct 1 ms 472 KB Output is correct
9 Correct 1 ms 348 KB Output is correct
10 Correct 1 ms 348 KB Output is correct
11 Incorrect 1 ms 348 KB Output isn't correct
12 Halted 0 ms 0 KB -