BOX REDUCTION

Rohit has n empty boxes lying on the ground in a line. The size of the boxes is given in the form of an array $a$. The size of the ith box is denoted by $a[i]$. Since Rohit has a tiny room, there is a shortage of space. Therefore, he has to reduce the number of boxes on the ground by putting a box into another box that is at least twice the size of the current box i.e if we have to put the ith box