Salome is a lovely girl, and she is a extreme fan of milk tea. She is a super VIP of Coco, and now she wants to reach all the Coco shops in the world. All the Coco shops are connected as a tree, and the root is the **head office**. If there is a road between two Coco shops, Salome can go from one to another cost 1. Salome can also go back to **head office** immediately from any shop cost 0. Initially, Salome go from the **head office**(node 1), but Salome is short with algorithms. She wants to know the minimum cost if she want to reach all the shops, please tell her the minimum cost.