Add additional

1 files changed, 54 insertions, 0 deletions

diff --git a/Additional/reverse-nodes-in-k-group.cpp b/Additional/reverse-nodes-in-k-group.cpp
new file mode 100644
index 0000000..70b63fd
--- /dev/null
+++ b/Additional/reverse-nodes-in-k-group.cpp
@@ -0,0 +1,54 @@
+#include<iostream>
+#include"../Seminar04/linked-list-utils.h"
+
+using ListNode = LinkedListNode<int>;
+
+ListNode* getNext(ListNode* head, int k) {
+    while(k && head) {
+        head = head->next;
+        --k;
+    }
+
+    return head;
+}
+
+ListNode* reverse(ListNode*& head) {
+    ListNode* next = nullptr;
+    ListNode* prev = nullptr;
+    ListNode* it = head;
+    ListNode* tmp = head;
+
+    while(it) {
+        next = it->next;
+        it->next = prev;
+        prev = it;
+        it = next;
+    }
+
+    head = prev;
+    return tmp;
+}
+
+ListNode* reverseKGroup(ListNode* head, int k) {
+    ListNode* end = getNext(head, k - 1);
+
+    if(end == nullptr)
+        return head;
+
+    ListNode* next = end->next;
+
+    end->next = nullptr;
+    
+    ListNode* last = reverse(head);
+    ListNode* res = reverseKGroup(next, k);
+
+    last->next = res;
+    return head;
+}
+
+int main() {
+    ListNode* ll = fromList({1, 2, 3, 4, 5, 6, 7,8 ,9,10, 11, 12, 13, 14, 15, 16, 17});
+    ll = reverseKGroup(ll, 4);
+    printLinkedList(ll);
+    freeList(ll);
+}
\ No newline at end of file