day 11: 328-odd-even-linked-list

328-odd-even-linked-list/driver.cpp

@@ -0,0 +1,22 @@
+#include "soln.hpp"
+
+int main()
+{
+	ListNode n5 = ListNode(5);
+	ListNode n4 = ListNode(4, &n5);
+	ListNode n3 = ListNode(3, &n4);
+	ListNode n2 = ListNode(2, &n3);
+	ListNode n1 = ListNode(1, &n2);
+	
+	ListNode n_4 = ListNode(4);
+	ListNode n_2 = ListNode(2, &n_4);
+	ListNode n_5 = ListNode(5, &n_2);
+	ListNode n_3 = ListNode(3, &n_5);
+	ListNode n_1 = ListNode(1, &n_3);
+	
+	Solution soln;
+	soln.printList(&n1);
+	soln.printList(&n_1);
+	cout << "Grouped odd-even correctly? " << soln.test(&n1, &n_1) << endl;
+	return 0;
+}

328-odd-even-linked-list/soln.cpp

@@ -0,0 +1,51 @@
+#include "soln.hpp"
+
+ListNode *Solution::oddEvenList(ListNode *head)
+{
+	bool odd_node = true;
+	if (head == nullptr || head->next == nullptr || head->next->next == nullptr)
+		return head;
+	ListNode *even_start = head->next;
+	ListNode *cur_node;
+	ListNode *next_node = head;
+	while (next_node)
+	{
+		cur_node = next_node;
+		next_node = cur_node->next;
+		if (next_node == nullptr)
+			break;
+		cur_node->next = cur_node->next->next;
+	}
+	cur_node = head;
+	while (cur_node->next)
+		cur_node = cur_node->next;
+	cur_node->next = even_start;
+	return head;
+}
+
+void Solution::printList(ListNode *head)
+{
+	ListNode *cur = head;
+	while (cur)
+	{
+		cout << cur->val << " ";
+		cur = cur->next;
+	}
+	cout << endl;
+}
+
+bool Solution::test(ListNode *head, ListNode *answer)
+{
+	ListNode *cur1 = oddEvenList(head), *ans1 = answer;
+	while (cur1 && ans1)
+	{
+		if (cur1->val != ans1->val)
+			return false;
+		cur1 = cur1->next;
+		ans1 = ans1->next;
+	}
+	if (!cur1 && !ans1)
+		return true;
+	else
+		return false;
+}

328-odd-even-linked-list/soln.hpp

@@ -0,0 +1,20 @@
+#include <bits/stdc++.h>
+
+using namespace std;
+
+/* 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* oddEvenList(ListNode* head);
+		void printList(ListNode* head);
+		bool test(ListNode* head, ListNode* answer);
+};