Submission #485105

#	Time	Username	Problem	Language	Result	Execution time	Memory
485105		largefence	Balloons (CEOI11_bal)	C++17	100 / 100	144 ms	6448 KiB

bal

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

#define pw2(x) ((x)*(x))

double x[200000], r[200000], pck[200000];
int main() {
    //ios::sync_with_stdio(false);
    //cin.tie(0);
    //freopen("ws.INP", "r", stdin);
	//freopen("ws.OUT", "w", stdout);

	int n; scanf("%d", &n);
	for (int i = 0; i < n; i++)
        scanf("%lf %lf", &x[i], &r[i]);//cin >> x[i] >> r[i];
    pck[0] = r[0]; printf("%.3lf\n", pck[0]);
    stack<int> st; st.push(0);
    for (int i = 1; i < n; i++) {
        pck[i] = r[i];
        /*
        if distance between 2 center < sum of rad of circles => intersect
        ^ <=> sqrt((x[i] - x[j])^2 + (h[i] - h[j])^2) == h[i] + h[j] => maximal
        */
        while (!st.empty()) {
            int j = st.top();
            double res = pw2(x[i] - x[j]) / (4.0 * pck[j]);
            pck[i] = min(pck[i], min(r[i], res));
            if (pck[i] >= pck[j]) st.pop();
            else break;
        } st.push(i);
        printf("%.3lf\n", pck[i]);
    }
    return 0;
}

// How to AC ?

Compilation message (stderr)

bal.cpp: In function 'int main()':
bal.cpp:13:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   13 |  int n; scanf("%d", &n);
      |         ~~~~~^~~~~~~~~~
bal.cpp:15:14: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
   15 |         scanf("%lf %lf", &x[i], &r[i]);//cin >> x[i] >> r[i];
      |         ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~

• 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