LeetCode - Convert Binary Number in a Linked List to Integer Solution - The Coding Shala

Home >> LeetCode >> convert binary number in a linked list to integer

 In this post, we will learn how to solve LeetCode's Convert Binary Number in a Linked List to Integer problem and will implement Java Solution.

Convert Binary Number in a Linked List to Integer Problem

Given head which is a reference node to a singly-linked list. The value of each node in the linked list is either 0 or 1. The linked list holds the binary representation of a number.
Return the decimal value of the number in the linked list.

Example 1:
Input: head = [1,0,1]
Output: 5
Explanation: (101) in base 2 = (5) in base 10

Example 2:
Input: head = [0]
Output: 0

Example 3:
Input: head = [1,0,0,1,0,0,1,1,1,0,0,0,0,0,0]
Output: 18880

Convert Binary Number in a Linked List to Integer Java Solution

Approach 1:
We can solve this using extra memory. First will take all data from the linked list and move to ArrayList then we can change it to decimal.

Java Program: 

 * Definition for singly-linked list.
 * public class ListNode {
 *     int val;
 *     ListNode next;
 *     ListNode() {}
 *     ListNode(int val) { this.val = val; }
 *     ListNode(int val, ListNode next) { this.val = val; this.next = next; }
 * }
class Solution {
    public int getDecimalValue(ListNode head) {
        ArrayList<Integer> arr = new ArrayList<>();
        while(head != null) {
            head = head.next;
        int len = arr.size();
        int dec = 0;
        int two = 1;
        for(int i = len-1; i>=0; i--) {
            dec += (arr.get(i) * two);
            two *= 2;
        return dec;

Other Posts You May Like
Please leave a comment below if you like this post or found some error, it will help me to improve my content.


Popular Posts from this Blog

Shell Script to find sum, product and average of given numbers - The Coding Shala

Shell Script to Create a Simple Calculator - The Coding Shala

Add two numbers in Scala - The Coding Shala

New Year Chaos Solution - The Coding Shala

Richest Customer Wealth LeetCode Solution - The Coding Shala