Submission #648772

#	Submission time	Handle	Problem	Language	Result	Execution time	Memory
648772	2022-10-08T08:10:42 Z	wyhong3103	Balloons (CEOI11_bal)	C++14	100 / 100	1675 ms	15288 KB

#include <bits/stdc++.h>
#define all(x) begin(x),end(x)
#define fir first
#define sec second
#define sz(x) x.size()
#define pb push_back
 
using namespace std;
using ll = long long;
using vi = vector<int>;
using pi = pair<int,int>;
using db = double;
using ldb = long double;
using pldb = pair<ldb, ldb>;
using pdb = pair<db,db>;
using pll = pair<ll,ll>;
using vll = vector<ll>;
const double EPS = (1e-6);
 
void setio(string s){
    freopen((s + ".in").c_str(),"r",stdin);
    freopen((s + ".out").c_str(),"w",stdout);
}

ldb dist(pldb a, pldb b){
    return hypot(abs(a.fir-b.fir), abs(a.sec-b.sec));
}

void solve(){
    int n;
    cin >> n;

    vector<pldb> a(n);
    for(auto& i : a) cin >> i.fir >> i.sec;

    vector<ldb> res(n);

    //{loc, radius}, monotonic radius
    stack<pldb> s;
    

    for(int i{}; i < n; i++){
        ldb cur_hi = a[i].sec;
        while (!s.empty()){
            ldb lo = 0, hi = cur_hi;
            for(int j{}; j < 50; j++){
                ldb mid = lo + (hi-lo)/2; 
                if (dist(s.top(), {a[i].fir, mid}) > mid+s.top().sec) lo = mid;
                else hi = mid;
            }
            cur_hi = lo;
            if (lo > s.top().sec){
                s.pop(); 
            }else break;
        }

        res[i] = cur_hi;
        s.push({a[i].fir, cur_hi});
    }
    cout << setprecision(8) << fixed;
    for(auto& i : res) cout << i << '\n';
}

int main(){
    ios_base::sync_with_stdio(false);
    cin.tie(nullptr);
    int t = 1;
    while(t--){
        solve();
    }
    return 0;
}

Compilation message

bal.cpp: In function 'void setio(std::string)':
bal.cpp:21:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   21 |     freopen((s + ".in").c_str(),"r",stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
bal.cpp:22:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   22 |     freopen((s + ".out").c_str(),"w",stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Subtask #1
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1 ms	212 KB	10 numbers

Subtask #2
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	0 ms	212 KB	2 numbers

Subtask #3
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	5 ms	356 KB	505 numbers

Subtask #4
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	19 ms	436 KB	2000 numbers

Subtask #5
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	176 ms	1412 KB	20000 numbers

Subtask #6
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	421 ms	3804 KB	50000 numbers
2	Correct	425 ms	3232 KB	49912 numbers

Subtask #7
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	856 ms	6604 KB	100000 numbers

Subtask #8
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	975 ms	7596 KB	115362 numbers
2	Correct	1054 ms	7296 KB	119971 numbers

Subtask #9
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1308 ms	9888 KB	154271 numbers
2	Correct	1662 ms	15288 KB	200000 numbers

Subtask #10
10.0 / 10.0

#	Verdict	Execution time	Memory	Grader output
1	Correct	1675 ms	12380 KB	200000 numbers
2	Correct	1668 ms	11948 KB	199945 numbers