Print a star pyramid composed of symbol *.
The first layer is *.
The second layer is **.
.
The N layer is supposed to have n star.
The N+1 layer is supposed to have n-1 star.
.
The 2N-1 layer is *.
Input N to decide how many layers to print.
Star pyramid.
Detail will show in sample output.
Remember put "\n" at the end of each line.