Everyone know the story that how Newton discovered the Universal Gravitation. One day, Newton walked

leisurely, suddenly, an apple hit his head. Then Newton discovered the Universal Gravitation.From then

on,people have sovled many problems by the the theory of the Universal Gravitation. What's more, wo also

have known every object has its Center of Gravity.

Now,you have been given the coordinates of three points of a triangle. Can you calculate the center

of gravity of the triangle?

For each case, print the coordinate, accurate up to 1 decimal places.