Little Galileo enjoys throwing stones. But with his scientific mind and poor eyesight he doesn't throw them at targets. Instead he leans out
of the windows and balconies of various buildings and tries to throw the stones upwards. Of course due to gravity
they soon changes direction and fall to the ground. You are to calculate the stone "fly time" in seconds, given its initial speed V (upwards)
and the height H of the window, from which the stone is thrown.
Example with numbers:
V = 10 m/s
H = 5 meters
should give result about 2.45 seconds.