![\"\"](\"https:\/\/prepbytes-misc-images.s3.ap-south-1.amazonaws.com\/assets\/1644922247901-91.Print-reverse-04.png\")
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Given a singly linked list. Write a function to print it in reverse order. The only restriction is that you can\u2019t reverse the original linked list.<\/p>\n<\/p>\n
Let us understand this problem with an example:
\nLet\u2019s say we have the given linked list as,<\/p>\n
![\"\"](\"https:\/\/prepbytes.com\/blog\/wp-content\/uploads\/2021\/08\/resultant-linked-list-2.png\")
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According to the problem we need to print it in reverse order. Reverse order means we have to print the values of nodes from right to left.<\/p>\n
So the desired output for this linked list will be 5 4 3 2 1.<\/p>\n
We need to do this without reversing the given linked list.<\/p>\n
Hope that you have understood the problem. Now try to come up with an approach.<\/p>\n
If we were allowed to reverse the linked list, then it would be simple. But here we aren\u2019t allowed to do so. So, try to think how we should approach this problem?<\/p>\n
Let\u2019s see how a stack works.<\/p>\n
It follows the LIFO(last in first out) principle. This means the element inserted most recently will come out first. And similarly, if we extract elements from the stack, we will get them in the reverse order of insertion. This is exactly what we need.<\/p>\n
So, due to its LIFO property, a stack is able to store elements in reverse order of their insertion and hence can be used to solve our problem.<\/p>\n
We can simply traverse the linked list and push the value stored in the nodes one by one into the stack. When the traversal is complete, we would have the linked list\u2019s data in reverse order in the stack. Now, we can, one by one, extract the top element from the stack and print them and then pop the elements from the stack.<\/p>\n
![\"\"](\"https:\/\/prepbytes.com\/blog\/wp-content\/uploads\/2021\/08\/Print-Reverse-Of-A-Linked-List-Without-Actually-Reversing-it-1-01-1.png\")
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