Initial commit

2026-03-18 00:57:17 +00:00 · 2022-07-26 16:15:18 +05:30
commit cef4c4dcc4
65 changed files with 1806 additions and 0 deletions
--- a/Easy/linked-list-cycle/solution.cpp
+++ b/Easy/linked-list-cycle/solution.cpp
@@ -0,0 +1,50 @@
+#include <iostream>
+#include <unordered_map>
+
+struct ListNode {
+    int val;
+    ListNode *next;
+    ListNode(int x) : val(x), next(NULL) {}
+};
+
+class Solution {
+  public:
+    // bool hasCycle(ListNode *head) {
+    //     std::unordered_map<ListNode *, int> hmap;
+    //     ListNode *curr = head;
+    //     while (curr != NULL) {
+    //         if (++hmap[curr] == 2) {
+    //             return true;
+    //         } else {
+    //             curr = curr->next;
+    //         }
+    //     }
+    //
+    //     return false;
+    // }
+
+    bool hasCycle(ListNode *head) {
+        if (head == NULL) {
+            return false;
+        }
+
+        ListNode *slow = head, *fast = head;
+        int taken = 0, limit = 2;
+
+        while (fast->next != NULL) {
+            fast = fast->next;
+            ++taken;
+            if (slow == fast) {
+                return true;
+            }
+
+            if (taken == limit) {
+                taken = 0;
+                limit *= 2;
+                slow = fast;
+            }
+        }
+
+        return false;
+    }
+};