Learning Journal

1/22/2024

Print Immutable Linked List in Reverse

/**
 * // This is the ImmutableListNode's API interface.
 * // You should not implement it, or speculate about its implementation
 * class ImmutableListNode {
 *      printValue() {}
 *
 *      getNext(): ImmutableListNode {}
 * }
 */

function printLinkedListInReverse(head: ImmutableListNode) {

    _print(head);

};

function _print(node: ImmutableListNode | null) {

    if (node === null) return;

    _print(node.getNext());

    node.printValue();

}/**
 * // This is the ImmutableListNode's API interface.
 * // You should not implement it, or speculate about its implementation
 * class ImmutableListNode {
 *      printValue() {}
 *
 *      getNext(): ImmutableListNode {}
 * }
 */

function printLinkedListInReverse(head: ImmutableListNode) {

    _print(head);

};

function _print(node: ImmutableListNode | null) {

    if (node === null) return;

    _print(node.getNext());

    node.printValue();

}

This problem is relatively simple to solve. Basically, you recursively traverse to the end of the list, then, print each element on the way back.

I found this problem under the Stack category because I wanted to practice some Stack problems, but then I figured using recursion is faster, and furthermore, recursion actually uses stack under the hood.