cs2370 Notes: 07 Lists

def process(xs: list[int]):
    for xx in xs:
       ... xx ...

If we have a list of things, we want to loop through the list and do something with each thing.

def mutate_list(xs: list[int]):
    """Change the elements of the list in place."""
    for ii in range(0, len(xs))
        xx = xs[ii]
        xs[ii] = ... xx ...

If you need to alter the elements an existing list, this pattern gives you the list indices which are nesisary to do that.

Standard pattern for returning a list

def produce() -> list[int]:
    ys = []
    return ys

To return a list, we want to first build a list and then return it.

def rabbit(xx: int) -> list[int]:
    ys = []
    ys.append(xx)
    return ys

Stuff to do:

Sum
Smallest
Differences (list of tuple -> list of int)

(pennies, nickles, dimes, quarters)