Neznaika and Gunka decided to meet to go visit Knopochka. They ran out of their houses at the same time to meet each other. Neznaika ran with speed V_{1} meters per second, and Gunka with speed V_{2} meters per second. In how many seconds they will meet if the distance between their houses is S meters.

Input format
Given are three real numbers S, V_{1}, V_{2}, каждое на отдельной строке.

Output format
Outpur the answer to the problem with an accuracy of at least 6 decimal places.