Submission #1100292

#	Time	Username	Problem	Language	Result	Execution time	Memory
1100292		michified	Balloons (CEOI11_bal)	C++17	50 / 100	2066 ms	8800 KiB

bal

#include <bits/stdc++.h>
#define ll long long
#define db double
#define lid id * 2 + 1
#define rid id * 2 + 2
using namespace std;

const ll mod = 1e9 + 7;

db bestR(db x1, db r1, db x2, db r2) {
    db l = 0, r = r2 + 1;
    while (l < r - 0.0000000001) {
        db mid = (l + r) / 2;
        if (sqrt((x2 - x1) * (x2 - x1) + abs(r1 - mid) * abs(r1 - mid)) >= r1 + mid) l = mid;
        else r = mid;
    }
    return min(r2, l);
}

int main() {
    // ifstream cin("balancing.in");
    // ofstream cout("balancing.out");

    int n, i;
    cin >> n;
    vector<db> x(n), r(n);
    for (i = 0; i < n; i++) cin >> x[i] >> r[i];
    vector<db> ans(n);
    stack<int> st;
    ans[0] = r[0];
    st.push(0);
    for (i = 1; i < n; i++) {
        db res = r[i];
        while (not st.empty()) {
            res = min(res, bestR(x[st.top()], ans[st.top()], x[i], r[i]));
            if (res >= ans[st.top()]) st.pop();
            else break;
        }
        ans[i] = res;
        st.push(i);
    }
    cout << fixed << setprecision(3);
    for (i = 0; i < n; i++) cout << ans[i] << endl;
    return 0;
}

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