leetcode-problemset/leetcode-cn/problem (English)/链表求和(English) [sum-lists-lcci].html

<p>You have two numbers represented by a linked list, where each node contains a single digit. The digits are stored in reverse order, such that the 1&#39;s digit is at the head of the list. Write a function that adds the two numbers and returns the sum as a linked list.</p>



<p>&nbsp;</p>



<p><strong>Example: </strong></p>



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<strong>Input: </strong>(7 -&gt; 1 -&gt; 6) + (5 -&gt; 9 -&gt; 2). That is, 617 + 295.

<strong>Output: </strong>2 -&gt; 1 -&gt; 9. That is, 912.

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<p><strong>Follow Up:&nbsp;</strong>Suppose the digits are stored in forward order. Repeat the above problem.</p>



<p><strong>Example: </strong></p>



<pre>

<strong>Input: </strong>(6 -&gt; 1 -&gt; 7) + (2 -&gt; 9 -&gt; 5). That is, 617 + 295.

<strong>Output: </strong>9 -&gt; 1 -&gt; 2. That is, 912.

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