标签:present ted dia lis dom repr ber solution tps
Problem:
A linked list is given such that each node contains an additional random pointer which could point to any node in the list or null.
Return a deep copy of the list.
The Linked List is represented in the input/output as a list of n nodes. Each node is represented as a pair of [val, random_index]
where:
val
: an integer representing Node.val
random_index
: the index of the node (range from 0
to n-1
) where random pointer points to, or null
if it does not point to any node.Example 1:
Input: head = [[7,null],[13,0],[11,4],[10,2],[1,0]]
Output: [[7,null],[13,0],[11,4],[10,2],[1,0]]
Example 2:
Input: head = [[1,1],[2,1]]
Output: [[1,1],[2,1]]
Example 3:
Input: head = [[3,null],[3,0],[3,null]]
Output: [[3,null],[3,0],[3,null]]
Example 4:
Input: head = []
Output: []
Explanation: Given linked list is empty (null pointer), so return null.
Constraints:
-10000 <= Node.val <= 10000
Node.random
is null or pointing to a node in the linked list.Number of Nodes will not exceed 1000.
思路:
Solution:
Node* copyRandomList(Node* head) {
Node *newHead, *l1, *l2;
if (head == NULL) return NULL;
for (l1 = head; l1 != NULL; l1 = l1->next->next) {
l2 = new Node(l1->val);
l2->next = l1->next;
l1 -> next = l2;
}
newHead = head->next;
for (l1 = head; l1 != NULL; l1 = l1->next->next) {
if (l1->random != NULL) l1->next->random = l1->random->next;
}
for (l1 = head; l1 != NULL; l1 = l1->next) {
l2 = l1->next;
l1->next = l2->next;
if (l2->next != NULL) l2->next = l2->next->next;
}
return newHead;
}
性能:
Runtime: 12 ms??Memory Usage: 13.3 MB
138. Copy List with Random Pointer
标签:present ted dia lis dom repr ber solution tps
原文地址:https://www.cnblogs.com/dysjtu1995/p/12275040.html