1.题目要求:
2.题目代码:
/**
* Definition for singly-linked list.
* struct ListNode {
* int val;
* ListNode *next;
* ListNode() : val(0), next(nullptr) {}
* ListNode(int x) : val(x), next(nullptr) {}
* ListNode(int x, ListNode *next) : val(x), next(next) {}
* };
*/
class Solution {
public:
//设置数组,把链表的结点存入数组中
vector<int> array;
Solution(ListNode* head) {
ListNode* cur = head;
while(cur){
array.push_back(cur->val);
cur = cur->next;
}
//设置随机种子
srand((unsigned)time(NULL));
}
int getRandom() {
//控制随机范围
int randomindex = rand() % array.size();
return array[randomindex];
}
};
/**
* Your Solution object will be instantiated and called as such:
* Solution* obj = new Solution(head);
* int param_1 = obj->getRandom();
*/