Code: Select all

```
def triangle(n):
return recursive_triangle(n, n)
def recursive_triangle(x, n):
# First we must verify that both input values are integers.
if type(x) != int or type(n) != int:
return 'error'
# If x is bigger than n, we will still only print the full triangle, so we can set them equal.
if x > n:
x = n
# If either value is zero, the output should be an empty string because there are no lines or triangle to print.
if x == 0 or n == 0:
return ''
# Let's set some variable names to help us out.
star_print = n
line_number = x
# I'll create an empty string that we can concatenate values to.
line_print = ''
# The difference value will determine how many shapes are needed to fill the line before the stars are printed.
difference = star_print - line_number
# If difference is not zero, we will print that value of spaces before the stars. The star print will be the
# remainder, also known as line number.
if difference != 0:
line_print += ' '*difference
line_print += '*'*line_number
# If difference is zero, then we can just fill the line with stars.
else:
line_print += '*'*star_print
# If the line number is greater than one, we can return our string and use the recursive call to run the function
# again with the line number as one value less.
if line_number > 1:
return line_print+'\n'+str(recursive_triangle(line_number-1, star_print))
# If the line number is exactly one, then we don't need to use the recursive call.
elif line_number == 1:
return line_print
```