1290. Convert Binary Number in a Linked List to Integer -with java- (leetcode.com)

Solution.java

/*
Your runtime beats 100.00 % of java submissions.
Your memory usage beats 83.62 % of java submissions.
*/

/**
 * 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) {
        int sum=0;
        do{
            sum = sum*2 + head.val;
            head = head.next;
        }while(head!=null);
        return sum;
    }
}