Leetcode题解之 —— 两数相加

思路

  • 多指针
  • 对应相加
  • 注意增量

题解

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/**
 * @param {ListNode} l1
 * @param {ListNode} l2
 * @return {ListNode}
 */
var addTwoNumbers = function(l1, l2) {
  const result = new ListNode(0);
  let [current, incremental] = [result, 0];

  while (l1 || l2) {
    const [v1, v2] = [
      l1 ? l1.val : 0,
      l2 ? l2.val : 0,
    ];

    const sum = v1 + v2 + incremental;
    current = current.next = new ListNode(sum % 10);
    incremental = ~~(sum / 10);

    [l1, l2] = [l1 ? l1.next: null, l2 ? l2.next : null];
  }

  if (incremental) {
    current.next = new ListNode(incremental);
  }

  return result.next;
};