lst = [ "a", "b", "c"]
print(lst)
lst[1] = "foo"
print(lst)
lst.append("zoo")
print(lst)

###

# Destructive

def destructiveDouble(lst):
    for i in range(len(lst)):
        lst[i] = lst[i] * 2
    return None

x = [1, 2, 3]
destructiveDouble(x)
print(x)

# Non-destructive

def nonDestructiveDouble(lst):
    result = []
    for i in range(len(lst)):
        result.append(lst[i] * 2)
    return result

x = [1, 2, 3]
y = nonDestructiveDouble(x)
print(x, y)