s0024

src/s0024_swap_nodes_in_pairs.cpp

@@ -0,0 +1,11 @@
+#include "s0024_swap_nodes_in_pairs.hpp"
+
+ListNode* swapPairs(ListNode* head) {
+  if (head == nullptr || head->next == nullptr) {
+    return head;
+  }
+  ListNode *newHead = head->next;
+  head->next = swapPairs(newHead->next);
+  newHead->next = head;
+  return newHead;
+}