Takes array as parameter and returns a reverse array using loop-CodePudding

# Function that takes array as parameter and returns a reverse array 
# using loop

def reverse_list(arr = []):
    for i in arr[::-1]:
        print(i)
arr_num = [1, 2, 3, 4, 5]

print(reverse_list(arr_num))

I want my function to take an array as a parameter, but I'm not sure if the structure /code of it is correct.

CodePudding user response：

Simply create a new array inside the function and either append each values before returning it

def reverse_list(arr = []):
    new_arr = []
    for i in arr[::-1]:
        # print(i)
        new_arr.append(i)
    return new_arr


arr_num = [1, 2, 3, 4, 5]

print(reverse_list(arr_num))

Or in short assign the reversed array to the new array

def reverse_list(arr = []):
    new_arr = arr[::-1]
    return new_arr

CodePudding user response：

Your function will not work since it's not returning the list.

Here is one way to solve this problem:

def reverse_list(arr):
    result = []
    
    for i, _ in enumerate(arr):    # try to use enumerate - it's better
        result.append(arr[~i])     # use the backward indexing here
        
    return result

CodePudding user response：

you can simply use the reversed builtin function;

>>> reversed([1,2,3,4])
[4,3,2,1]

but if you wanted to have a function to return it, i will advise to use the slice indexing:

def rev_list(lst):
    return lst[::-1]