Submission #1116637

#	Time	Username	Problem	Language	Result	Execution time	Memory
1116637		pemguimn	Balloons (CEOI11_bal)	C++17	100 / 100	124 ms	11332 KiB

bal

#include <bits/stdc++.h>

using namespace std;

const int N = 2e5 + 5;

int n, x[N], r[N];

long double ans[N];

long double calc(int i, int j){
    long double x1 = x[i], y1 = ans[i];
    long double x2 = x[j];
    return (x1 * x1 + x2 * x2 - 2.0L * x1 * x2 ) / (4.0L * y1);
}

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

    cin >> n;
    for(int i = 1; i <= n; i++){
        cin >> x[i] >> r[i];
        ans[i] = r[i];
    }

    stack<int> st;
    for(int i = 1; i <= n; i++){
        long double reach = r[i];
        while(st.size()){
            reach = min(reach, calc(st.top(), i));
            if(reach < ans[st.top()]) break;
            st.pop();
        }       
        ans[i] = reach;
        st.push(i);
    }

    for(int i = 1; i <= n; i++)
        cout << setprecision(9) << fixed << ans[i] << "\n";

    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