go: add «2181. Merge Nodes in Between Zeros»

Signed-off-by: Matej Focko <me@mfocko.xyz>

go/merge-nodes-in-between-zeros.go

@@ -0,0 +1,18 @@
+package main
+
+func mergeNodes(head *ListNode) *ListNode {
+	head = head.Next
+	if head == nil {
+		return nil
+	}
+
+	node := head.Next
+	for node.Val != 0 {
+		head.Val += node.Val
+		node = node.Next
+	}
+
+	head.Next = mergeNodes(node)
+
+	return head
+}