# Exercice 1
p = creer_pile()
# Pile vide
p.empile(5)
# |5|
p.empile(3)
# |3|
# |5|
p.empile(7)
# |7|
# |2|
# |5|
p.depile()
# |3|
# |5|
p.depile()
# |5|
p.empile(4)
# |4|
# |5|
p.empile(2)
# |2|
# |4|
# |5|
p.depile()
# |4|
# |5|
p.depile()
# |5|