题解:
我是直接逆转链表,然后按照二进制和十进制的转换关系求的,实际上还有很多方法。
代码:
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode(int x) : val(x), next(NULL) {}
* };
*/
class Solution {
public:
int getDecimalValue(ListNode* head) {
ListNode* head2 = reverse(head);
int sum = 0; int tmp = 0;
while(head2)
{
sum += head2->val * pow(2,tmp++);
head2 = head2->next;
}
return sum;
}
ListNode* reverse(ListNode* head)
{
if(head == NULL || head->next == NULL)
{
return head;
}
ListNode* res = reverse(head->next);
head->next->next = head;
head->next = NULL;
return res;
}
};