How to compare and copy the value of one vector to another?

I have a VECTOR A = [0,540] and B = [60,600,15]

Lets say i have

                index = 1 for A(1) = 0
                index = 3 for A(2) = 540
So
 it should A vector should compare with B
 *index 1 of A = index 1 of B
 index 3 of A = index 3 of B
But index 2 of A IS NOT PRESENT SO IT  SHOULD TAKE INDEX 2 of B and put it in A as INDEX 2 of A*

SO FINAL OUTPUT SHOULD BE LIKE THIS: A = [0,600,540]

IF INDEX OF A VECTOR CHANGES THEN IT SHOULD TAKE APPROPRIATE INDEX WHICH IS MISSING in A and it should copy the missing index value from B vector AND ADD IT IN THAT PLACE!

[Image Analyst]

Sorry but index 2 of A IS present. It is 540 in your example. 540 is not index 3 as you said. I don't understand what rules you're trying to follow. And what is the role of the 15 in B? Does the 15 just get ignored? And is this your homework? It seems quirky enough of a request to be homework.

[Aswin Sandirakumaran]

Nope this isnt homework. It is just an idea to implement and use it my algorithm