luogu#P4697. [CEOI 2011] Balloons

    ID: 3686 远端评测题 2000ms 63MiB 尝试: 0 已通过: 0 难度: 8 上传者: 标签>计算几何2011Special JudgeCEOI(中欧)单调栈

[CEOI 2011] Balloons

Problem Description

There are nn balloons, and they are all empty at the beginning.

Next, they will be inflated one by one in order from 11 to nn. The ii-th balloon touches the ground at position xix_i.

A balloon stops inflating when it touches some previous balloon, or when it reaches its maximum radius limit. The maximum radius limit of the ii-th balloon is rir_i.

Now, please find the final radius of each balloon.

Input Format

The first line contains a positive integer nn, which represents the number of balloons.

The next nn lines each contain two integers xi,rix_i, r_i separated by a space.

Output Format

Output nn lines. Each line contains a floating-point number. The floating-point number on the ii-th line represents the final radius of the ii-th balloon.

Your answer will be judged correct if and only if the absolute error from the correct answer does not exceed 10310^{-3}.

3
0 9
8 1
13 7
9.000
1.000
4.694

Hint

For 100%100\% of the testdata, it is guaranteed that 1n2000001 \le n \le 200\,000, 0xi1090 \le x_i \le 10^9, 1ri1091 \le r_i \le 10^9, and x1<x2<<xnx_1 < x_2 < \cdots < x_n.

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