[Leetcode] 021. Merge Sorted Lists (Easy) (C++/python)

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Github:https://github.com/illuz/leetcode

021.merge_two_sorted_lists (Easy) links：

Title: https://oj.leetcode.com/problems/merge-two-sorted-lists/
Code (GitHub): Https://github.com/illuz/leetcode

Test Instructions：

Merges two ordered linked lists.

Analysis：

Very classic topic, but know how to do it easily, simulation can.
There are two ways of doing this:
1. Open a node to head the front node (the following Python code implementation)
2. Do not open directly (C + + code implementation)

Code：

C++:

Class Solution {Public:listnode *mergetwolists (ListNode *l1, ListNode *l2) {if (L1 = = null) return l2;if (L2 = null) re Turn L1; ListNode *start, *cur;if (L1->val < l2->val) {cur = start = L1;l1 = L1->next;} else {cur = start = L2;l2 = l2- >next;} while (L1 = null && L2! = null) {if (L1->val < l2->val) {Cur->next = L1;cur = L1;l1 = L1->next;} E LSE {Cur->next = L2;cur = L2;l2 = L2->next;}}    if (L1! = NULL) Cur->next = L1;elsecur->next = L2;return start; }}; ListNode *l1, *l2, *ll1, *ll2;int main () {int N1, n2; Solution s;cin >> n1;ll1 = L1 = new ListNode (0), for (int i = 0; i < N1; i++) {l1->next = new ListNode (0); L1 = L1-&GT;NEXT;SCANF ("%d", & (L1->val));} cin >> n2;ll2 = L2 = new ListNode (0), for (int i = 0; i < n2; i++) {l2->next = new ListNode (0); L2 = L2->next ; scanf ("%d", & (L2->val));} ListNode *res = s.mergetwolists (Ll1->next, Ll2->next); while (res! = NULL) {cout << res->val <<"; res = Res->next;} return 0;}

Python:

Class solution:    # @param listnodes    # @return a listnode    def mergetwolists (self, L1, L2):        if not L1 and Not L2:            return None        dummy = ListNode (0)        cur = dummy while        L1 and 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 or l2
   return Dummy.next

[Leetcode] 021. Merge Sorted Lists (Easy) (C++/python)