Formula to match repeating numbers

[Jordans121]

Lets say I have 3 cols with one number in each like below...

5 2 1
1 0 6
3 7 8
7 9 3

I want to compare the most "current" number (521) to the number before it (106) to see if any numbers repeated. In this case one number repeated which is "1".

So, I want the final output to be either 1 or 2 or 3