

'''simple docstring'''







from collections import defaultdict
def  UpperCAmelCase__      ( UpperCAmelCase__			)     ->     int:
       A_		   = 1
       A_		   = True
       for v in tree[start]:
              if v not in visited:
                     ret += dfs(_UpperCamelCase			)
       if ret % 2 == 0:
              cuts.append(_UpperCamelCase			)
       return ret
def  UpperCAmelCase__      ( )     ->     Optional[Any]:
       dfs(1			)


if __name__ == "__main__":
      __lowerCamelCase						    =     10, 9
      __lowerCamelCase						    =     defaultdict(list)
      __lowerCamelCase						    =     {}
      __lowerCamelCase						    =     []
      __lowerCamelCase						    =     0
      __lowerCamelCase						    =     [(2, 1), (3, 1), (4, 3), (5, 2), (6, 1), (7, 2), (8, 6), (9, 8), (10, 8)]
      for u, v in edges:
            tree[u].append(v)
            tree[v].append(u)
      even_tree()
      print(len(cuts) - 1)



'''simple docstring'''







def  UpperCAmelCase__      ( UpperCAmelCase__ = 10_00			)     ->     int:
       return sum(2 * a * ((a - 1) // 2) for a in range(3,    n + 1			)			)


if __name__ == "__main__":
      print(solution())
