Merge pull request #1197 from razer96/21-Merge-Two-Sorted-Lists.go

21-Merge-Two-Sorted-Lists go solution

Author: dissesmac

Diff for: go/21-Merge-Two-Sorted-Lists.go

@@ -0,0 +1,49 @@
+/**
+ * Definition for singly-linked list.
+ * type ListNode struct {
+ *     Val int
+ *     Next *ListNode
+ * }
+ */
+func mergeTwoLists(l1 *ListNode, l2 *ListNode) *ListNode {
+	if l1 == nil {
+		return l2
+	}
+
+	if l2 == nil {
+		return l1
+	}
+
+	ptr1, ptr2 := l1, l2
+
+	result := new(ListNode)
+
+	temp := result
+
+	for ptr1 != nil && ptr2 != nil {
+		if ptr1.Val < ptr2.Val {
+			temp.Next = ptr1
+			temp = temp.Next
+			ptr1 = ptr1.Next
+		} else {
+			temp.Next = ptr2
+			temp = temp.Next
+			ptr2 = ptr2.Next
+		}
+	}
+
+	for ptr1 != nil{
+		temp.Next = ptr1
+		temp = temp.Next
+		ptr1 = ptr1.Next
+	}
+
+	for ptr2 != nil{
+		temp.Next = ptr2
+		temp = temp.Next
+		ptr2 = ptr2.Next
+	}
+
+	result = result.Next
+	return result
+}