Deep inside a secure mountain facility there exists a group of switches arranged in a horizontal row. The rightmost switch can be flipped on or off at any time. Any other switch can be toggled only if the switch to its immediate right is turned on and all other switches to the right are turned off.
All the switches are initially off. Improvise a function that accepts the number
of switches, n, and returns the minimum number of switch toggles required to turn all the switches on.
switches(1) ➞ 1
switches(2) ➞ 2
switches(3) ➞ 5
// Minimal sequence for 3 switches:
// 000, 001, 011, 010, 110, 111
switches(4) ➞ 10
N/A