a = (1, 2, 3, 4, 5, 6)
b=list(a)
c=[]
for i in range(len(b)):
    c.append(b[0])
    if b[0]==b[-1]:
        break
    c.append(b[-1])
    b.pop(0)
    b.pop(-1)
    if not b:
        break
a=tuple(c)
print(a)

