Submission #941672

#	Time	Username	Problem	Language	Result	Execution time	Memory
941672		tnknguyen_	Balloons (CEOI11_bal)	C++14	100 / 100	613 ms	13660 KiB

bal

#include <bits/stdc++.h>
using namespace std;
#define endl '\n' 
#define pdd pair<long double, long double>

const int sz = 1e6 + 5;
pdd a[sz];
long double f[sz];

long double dist(long double x, long double y, long double u, long double v){
    x = x - u;
    y = y - v;

    return sqrt(x*x + y*y);
}

long double bs(pdd ball, long double p){
    long double l = 0, r = 1e9;
    long double x, y;
    tie(x, y) = ball;

    for(int i=1;i<=60;++i){
        long double mid = (l + r) / 2;
        if(dist(x, y, p, mid) >= mid + y){
            l = mid;
        }
        else{
            r = mid;
        }
    }

    return (l + r) / 2;
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);

//    freopen("main.inp","r",stdin);
//    freopen("main.out","w",stdout);

    int n;
    cin>>n;

    stack<int> st;
    for(int i=1;i<=n;++i){
        cin >> a[i].first >> a[i].second;    
        while(st.size()){
            a[i].second = min(a[i].second, bs(a[st.top()], a[i].first));
            if(a[i].second >= a[st.top()].second){
                st.pop();
            }
            else{
                break;
            }
        }
        st.push(i);
        cout<< fixed << setprecision(3) << a[i].second<<endl;
    }
    return 0;
}

• 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