### 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) { arr.add(head.val); 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**- LeetCode - Crawler Log folder
- LeetCode - Range Sum Query - Immutable
- LeetCode - Buddy Strings
- LeetCode - Shuffle Array
- LeetCode - Next Greater Element 1

## Comments

## Post a Comment