Submission #1116628

#	Time	Username	Problem	Language	Result	Execution time	Memory
1116628		pemguimn	Balloons (CEOI11_bal)	C++17	10 / 100	104 ms	6616 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){
    double x1 = x[i], y1 = ans[i];
    double x2 = x[j];
    return (x1 * x1 + x2 * x2 - 2 * x1 * x2 ) / (4 * 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];
        if(st.size()) reach = min(reach, calc(st.top(), i));
        ans[i] = reach;

        while(st.size() && calc(st.top(), i + 1) >= calc(i, i + 1)) st.pop();
        st.push(i);
    }
    while(st.size()){
        ans[n] = min(ans[n], calc(st.top(), n));
        st.pop();
    }

    for(int i = 1; i <= n; i++)
        cout << setprecision(3) << fixed << ans[i] << "\n";

    return 0;
}

• Subtask 1: 0 / 10
• Subtask 2: 10 / 10
• Subtask 3: 0 / 10
• Subtask 4: 0 / 10
• Subtask 5: 0 / 10
• Subtask 6: 0 / 10
• Subtask 7: 0 / 10
• Subtask 8: 0 / 10
• Subtask 9: 0 / 10
• Subtask 10: 0 / 10