Files
dsa-competitive-programming/leetcode/lc21/MergeLists.cpp
T
2026-02-11 14:56:22 +05:30

37 lines
856 B
C++

/**
* 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:
ListNode* mergeTwoLists(ListNode* l1, ListNode* l2) {
ListNode* dummy = new ListNode(0);
ListNode* cur = dummy;
while(l1 && l2){
if((l1->val) < (l2->val) ){
cur->next = l1;
l1 = l1->next;
}
else{
cur->next = l2;
l2 = l2->next;
}
cur = cur->next;
}
cur->next = l1? l1 : l2;
ListNode* head = dummy->next;
delete dummy;
return head;
}
};
// TC : O(m+n)
// SC : O(1)