Water Lily

题意翻译

现在有一朵长在水中的莲花,它露出水面的长度为H厘米(不包括花朵) 有人把它拽了L 厘米,使得茎秆部分恰好完全浸没于水中 现在给你H和L,请求水的深度

题目描述

While sailing on a boat, Inessa noticed a beautiful water lily flower above the lake's surface. She came closer and it turned out that the lily was exactly $ H $ centimeters above the water surface. Inessa grabbed the flower and sailed the distance of $ L $ centimeters. Exactly at this point the flower touched the water surface. ![](https://cdn.luogu.com.cn/upload/vjudge_pic/CF1199B/42f6cea9c2bcade7ac8750d98129857158bca8c3.png)Suppose that the lily grows at some point $ A $ on the lake bottom, and its stem is always a straight segment with one endpoint at point $ A $ . Also suppose that initially the flower was exactly above the point $ A $ , i.e. its stem was vertical. Can you determine the depth of the lake at point $ A $ ?

输入输出格式

输入格式


The only line contains two integers $ H $ and $ L $ ( $ 1 \le H < L \le 10^{6} $ ).

输出格式


Print a single number — the depth of the lake at point $ A $ . The absolute or relative error should not exceed $ 10^{-6} $ . Formally, let your answer be $ A $ , and the jury's answer be $ B $ . Your answer is accepted if and only if $ \frac{|A - B|}{\max{(1, |B|)}} \le 10^{-6} $ .

输入输出样例

输入样例 #1

1 2

输出样例 #1

1.5000000000000

输入样例 #2

3 5

输出样例 #2

2.6666666666667