Python programming functional vs. imperative code

Question

So I'm currently in a class learning about the 3 major programming paradigms. I know that python uses both the functional and imperative paradigms. I was looking for a short sample code in python of each of these paradigms to better understand this before my exam tomorrow. Thank you!

Accepted Answer

Given `L = [1, 2, 3, 4, 5]` we can compute the sum in two ways.

Imperative:

```
sum = 0
for x in L:
    sum += x
```

Functional (local function):

```
def add(x, y):
    return x + y
sum = reduce(add, L)
```

Functional (lambda expression):

```
sum = reduce(lambda x, y: x + y, L)
```

(Of course, the built in `sum` function would effectively do the same thing as either of these.)

Python programming functional vs. imperative code

Solution

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