#!/usr/bin/python
# -*- coding: utf-8 -*-

def en_sol_dip(myTree):
    sol = myTree[1]
    while True:
        if sol[1] == []:
            sol = sol[0]
            return sol
            break
        sol = sol[1]

myTree = ["a", #kok
            ["b", # sol altagac
               ["d",
                  ["h",
                    ["i",[],[]],
                    ["j",[],[]]
                  ]
               ],
               ["e",
                  ["g",[],[]],
                  []
               ]
            ],
            ["c", # sag altagac
               ["f",[],[]],
               []
            ]
          ]

print ("En sol dip:",en_sol_dip(myTree))