Get Minimum element in O(1) from input numbers

Question : Get Minimum element in O(1) from input numbers..

- With any traditional way we can't get minimum element in O(1)
- so we need to come up with different data structure.
- As its very old and famous question We are directly explaining logic

Logic 1)
Keep Two Stacks A and B.
A will contain all numbers which are input by users.
B will contain only minimum number from all input numbers.
ex. Input 10,20,5,30,2

Consider the following input
A                        B  (minimum elements)

2  --> TOP               2   ...
30                       5   ...
5                        5  (smallest in 10,20,5 input)
20                       10 (smallest in 10,20 input)
10                       10 (smallest at beginning) 

so as shown in figure B (minimum element stack will keep all smallest numbers wrt input)

Pros
- storing minimum element for each input.
- if current minimum element is popped , we still have minimum element in present stack

Cons
- O(n) Extra Space.
Thanks Dhaval for Code.
C Working Code : Find here : http://ideone.com/qOtFoG
C++ Working code : Find here : http://ideone.com/mgtTQY

Logic 2)

Instead of keeping a stack of minimum elements in B, we can optimism the solution with single minimum number.
B can be a pointer which always points to  Minimum value from inputted elements in A.
( Ba can be pointer type variable or even simple integer which stores index value "i" of minimum element in A )

Thanks Dhaval for suggesting Logic 2) & writing the code

Code Coming soon :