feat: saturday

pkg/linked_list_cycle/main.go

@@ -0,0 +1,28 @@
+package linked_list_cycle
+
+type ListNode struct {
+	Val  int
+	Next *ListNode
+}
+
+func succeed(n *ListNode) *ListNode {
+	if n == nil {
+		return n
+	} else {
+		return n.Next
+	}
+}
+
+func HasCycle(head *ListNode) bool {
+	one, two := head, succeed(head)
+
+	for one != nil && two != nil {
+		if one == two {
+			return true
+		}
+
+		one, two = succeed(one), succeed(succeed(two))
+	}
+
+	return false
+}