Create: 0206-reverse-linked-list.dart

priya-soni · Jan 6, 2023 · 3e19117 · 3e19117
1 parent bc10660
commit 3e19117
Showing 1 changed file with 25 additions and 0 deletions.
diff --git a/dart/0206-reverse-linked-list.dart b/dart/0206-reverse-linked-list.dart
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+// Time Complexity: O(n)
+// Space Complexity: O(1)
+
+class Solution {
+  ListNode? reverseList(ListNode? head) {
+    if (head == null) return null;
+
+    ListNode? newHead;
+
+    while (head != null) {
+      if (newHead == null) {
+        newHead = head;
+        head = head.next;
+        newHead.next = null;
+      } else {
+        var temp = newHead;
+        newHead = head;
+        head = head.next;
+        newHead.next = temp;
+      }
+    }
+
+    return newHead;
+  }
+}