Linked List Deletion - Amazon Top Interview Questions

Problem Statement :

Given a singly linked list node, and an integer target, return the same linked list with all nodes whose value is target removed.


n ≤ 100,000 where n is the number of nodes in node

Example 1


node = [0, 1, 1, 2]
target = 1


[0, 2]

Solution :


                        Solution in C++ :

** Recursive

LLNode* solve(LLNode* node, int target) {
    if(not node) return node;
    node->next = solve(node->next, target);
    return node->val == target ? node->next : node;

** Iterative

LLNode* solve(LLNode* head, int target) {
    auto* node = head;
    while (node) {
        while (node->next && node->next->val == target) {
            node->next = node->next->next;
        node = node->next;
    return (head->val == target ? head->next : head);

                        Solution in Java :

import java.util.*;

 * class LLNode {
 *   int val;
 *   LLNode next;
 * }
class Solution {
    public LLNode solve(LLNode node, int target) {
        LLNode prev = node;
        LLNode cur =;
        while (cur != null) {
            LLNode nxt =;
            if (cur.val == target)
       = nxt;
            else {
                prev = cur;
            cur = nxt;
        if (node.val == target)
        return node;

                        Solution in Python : 
class Solution:
    def solve(self, node, target):
        while node != None and node.val == target:
            node =
        ret = node
        while node != None:
            while != None and == target:
            node =
        return ret

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