2022.2.17
题目网址：
https://codeforces.com/contest/5/problem/D
题目：
Follow Traffic Rules
1000ms 65536K
描述：
Everybody knows that the capital of Berland is connected to Bercouver (the Olympic capital) by a direct road. To improve the road's traffic capacity, there was placed just one traffic sign, limiting the maximum speed. Traffic signs in Berland are a bit peculiar, because they limit the speed only at that point on the road where they are placed. Right after passing the sign it is allowed to drive at any speed.
It is known that the car of an average Berland citizen has the acceleration (deceleration) speed of a km/h2, and has maximum speed of v km/h. The road has the length of l km, and the speed sign, limiting the speed to w km/h, is placed d km (1?≤?d?<?l) away from the capital of Berland. The car has a zero speed at the beginning of the journey. Find the minimum time that an average Berland citizen will need to get from the capital to Bercouver, if he drives at the optimal speed.
The car can enter Bercouver at any speed.
输入：
The first line of the input file contains two integer numbers a and v (1?≤?a,?v?≤?10000). The second line contains three integer numbers l, d and w (2?≤?l?≤?10000; 1?≤?d?<?l; 1?≤?w?≤?10000).
输出：
Print the answer with at least five digits after the decimal point.
翻译：
描述：
每个人都知道贝兰的首都与柏库佛（奥林匹克首都）有一条直的马路相连。为了改善道路的交通能力，这里放了一个交通标志牌，上面是最大限速。在贝兰的交通标志牌有一点特别，因为他们只是在他们所放标志牌的那个地方限速。一过这个标志牌就允许车开到任何速度。
据了解，一个普通贝兰市民的小汽车加速（减速）速度为a km/h2，最大速度为v km/h。这条马路长l千米，速度标志牌限速w km/h，它被放在距离贝兰首都d（1>=d>l）千米处。汽车在旅途的开始有一个为0的速度。找到一个普通贝兰市民将需要从贝兰首都到柏库佛的最短时间，如果他以最佳的速度行驶。汽车可以以任何速度进入柏库佛。
输入：
输入数据的第一行包含两个整数a和v（1<=a,v<=10000）。第二行包含三个整数l,d和w（2<=l<=10000;1<=d<l;1<=w<=10000）。
输出：
打印出答案，答案保留小数后5位。