Submission #925561

#	Time	Username	Problem	Language	Result	Execution time	Memory
925561		May27_th	Balloons (CEOI11_bal)	C++17	100 / 100	140 ms	11892 KiB

bal

#include<bits/stdc++.h>
#define taskname "A"
using namespace std;

void World_Final();
void Solve();

int main(){
    ios_base::sync_with_stdio(false); cin.tie(nullptr);
    if (fopen(taskname".inp", "r")) {
        freopen(taskname".inp", "r", stdin);
        freopen(taskname".out", "w", stdout);
    }
    World_Final();
}

void World_Final(){
    int Tests = 1;
    //cin >> Tests;
    while (Tests --) {
        Solve();
    }
}

const int mod = 1e9 + 7;
struct ballon{
    int64_t x; long double r;
};

long double calc(int64_t d, long double r) {
    return 1.0 * d * d / (4 * r);
}

void Solve(){
     int N; cin >> N;
     vector<ballon> b(N);
     for (auto &[x, r] : b) cin >> x >> r;
     stack<pair<int64_t, long double>> s;
     for (int i = 0; i < N; i ++) {
        long double rmax = b[i].r;
        while (!s.empty()) {
            long double rmax_last = calc(b[i].x - s.top().first, s.top().second);
            rmax = min(rmax, rmax_last);

            if (rmax >= s.top().second) s.pop();
            else break;
        }
        cout << fixed << setprecision(3) << rmax << "\n";
        s.push(make_pair(b[i].x, rmax));
     }
}
/**
    A = I(i - 1, j), B = I(i, j - 1);
    |I(i, j)| = |A| + |B| - |A intersect B|











**/

Compilation message (stderr)

bal.cpp: In function 'int main()':
bal.cpp:11:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   11 |         freopen(taskname".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~
bal.cpp:12:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   12 |         freopen(taskname".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~

• 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