**Facebook hiring sample test**
There are K pegs. Each peg can hold discs in decreasing order
of radius when looked from bottom to top of the peg. There are N discs
which have radius 1 to N; Given the initial configuration of the pegs and
the final configuration of the pegs, output the moves required to transform
from the initial to final configuration. You are required to do the transformations
in minimal number of moves.
A move consists of picking the topmost disc of any one of the pegs and
placing it on top of another peg.
At any point of time, the decreasing radius property of all the pegs
must be maintained.
**Constraints:**
1<= N<=8
3<= K<=5
I**nput Format:**
N K
2nd line contains N integers.
Each integer in the second line is in the range 1 to K where the i-th
integer denotes the peg to which disc of radius i is present in the initial
configuration.
3rd line denotes the final configuration in a format similar to the
initial configuration.
**Output Format:**
The first line contains M - The minimal number of moves required
to complete the transformation.
The following M lines describe a move, by a peg number to pick from
and a peg number to place on.
If there are more than one solutions, it's sufficient to output any
one of them. You can assume, there is always a solution with less than
7 moves and the initial configuration will not be same as the final one.
Sample Input #00:
2 3
1 1
2 2
Sample Output #00:
3
1 3
1 2
3 2
Sample Input #01:
6 4
4 2 4 3 1 1
1 1 1 1 1 1
Sample Output #01:
5
3 1
4 3
4 1
2 1
3 1 |