1. Take 2 empty stacks.

2. Fill the 1st stack with some items (eg: input 100, 101, 102, 103)

3. Now read the items from 1st stack in LIFO order and write to 2nd stack.

(By this the 2nd stack will get the items in the order .. 103, 102, 101, 100)

4. Now read the items from 2nd stack in LIFO order i.e. the output will be

100, 101, 102, 103.

(this is the queue order FIFO with respect to the actual items entered in 1st

stack.)