Submission #1299536

#	Time	Username	Problem	Language	Result	Execution time	Memory
1299536		wojtekmal	Balloons (CEOI11_bal)	C++20	20 / 100	122 ms	5896 KiB

bal

#include <bits/stdc++.h>
using namespace std;

struct Ball
{
    double x, r;
};

int n;
vector<Ball> balls;

double sq(double a)
{
    return a * a;
}

double dist(Ball a, Ball b)
{
    return sqrt(sq(a.x - b.x) + sq(a.r - b.r));
}

double expected_r(Ball a, double x)
{
    return sq(x - a.x) / (4 * a.r);
}

void clean_balls(double x)
{
    while (balls.size() >= 2 && 
        expected_r(*(balls.end() - 1), x) >= expected_r(*(balls.end() - 2), x))
    {
        balls.pop_back();
    }
}

double get_r(double x, double max_r)
{
    clean_balls(x);
    if (balls.empty()) return max_r;
    return min(max_r, expected_r(balls.back(), x));
}

int main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout << fixed << setprecision(3);

    cin >> n;

    for (int i = 0; i < n; i++)
    {
        double x, max_r;
        cin >> x >> max_r;

        double r = get_r(x, max_r);
        cout << r << "\n";
        balls.push_back(Ball{x, r});
    }
}

• Subtask 1: 10 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10