x = [3, 4, 6, 8, 9, 10, 13, 14]
z1 = [0, 5, 7]
z2 = [1, 2, 6]

y = []
for i not in z1:
    y.append(x[i])

# Now I need to update the values of z2 ...

>> y
[4, 6, 8, 9, 13]
>> z2
[0, 1, 4]