input:
3
72
30
50

output:
120.00

But the task is to find the minimal weight!
I wonder how 120.00 (2*sqrt(72*50)) can be minimal? It's maximal!

Sorry, sample is ok, my thought is not ^^"

step #1 : 2*sqrt(72*50) =120  -->  colliding 72  and 50 and new stripy with weight 120
step #2 : 2*sqrt(120*30)=120  -->  colliding 120 and 30 and new stripy with weight 120