Submission #604051

#	Time	Username	Problem	Language	Result	Execution time	Memory
604051		chuangsheep	Balloons (CEOI11_bal)	C++11	100 / 100	218 ms	8612 KiB

bal

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

#define all(x) begin(x), end(x)
#define allr(x, r) begin(x), begin(x) + (r)

using ll = long long;
using ld = long double;

ld calc_r(pair<ld, ld> a, ld bx)
{
  return (a.first - bx) * (a.first - bx) / (4 * a.second);
}

int main()
{
#if defined(DEBUG) && !defined(ONLINE_JUDGE)
  // DEBUG
  cerr << "DEBUG flag set - see test.out for output\n";
  freopen("/home/chuang/shared-drives/G:/repos/cp/ois/ceoi11/balloons/test.in", "r", stdin);
  freopen("/home/chuang/shared-drives/G:/repos/cp/ois/ceoi11/balloons/test.out", "w", stdout);
#else
  cin.tie(0)->sync_with_stdio(false);
#endif

  int n;
  cin >> n;

  vector<ld> res(n);
  stack<pair<ld, ld>> to_check;
  for (int i = 0; i < n; i++)
  {
    ld x, r;
    cin >> x >> r;

    ld max_r = r;
    while (!to_check.empty())
    {
      pair<ld, ld> last = to_check.top();
      ld to_last_r = calc_r(last, x);
      max_r = min(max_r, to_last_r);

      if (max_r >= last.second)
      {
        to_check.pop();
        continue;
      }
      else
      {
        break;
      }
    }
    to_check.push({x,max_r});

    res[i] = max_r;
  }

  cout << fixed << setprecision(3);
  for (auto &r : res)
  {
    cout << r << "\n";
  }
}

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