Morgoth - 3 months ago 27

Python Question

Can you help to simplify this code and make it more efficient? Mine seems like it's not the best version; what can I improve?

`1`

232

34543

4567654

567898765

678901109876

This is the code I made:

`c = -1`

for y in range(1, 7):

print()

print((6-y) * " ", end="")

c += 1

for x in range(1, y+1):

print(y%10, end="")

y += 1

while y - c > 2:

print(y-2, end="")

y -= 1

Answer

First of all, I'm guessing that you didn't really want to print that **y** value of 10; that you really wanted the base-10 reduction to 0. Note that you have an extra character in the pyramid base.

Do *not* change the value of a loop parameter while you're inside the loop. Specifically, don't change y within the **for y** loop.

Get rid of **c**; you can derive it from the other values.

For flexibility, make your upper limit a parameter: you have two constants (6 and 7) that depend on one concept (row limit).

Here's my version:

```
row_limit = 7
for y in range(1, row_limit):
print()
print((row_limit-y-1) * " ", end="")
for x in range(y, 2*y):
print(x%10, end="")
for x in range(2*(y-1), y-1, -1):
print(x%10, end="")
print()
```

Output:

```
1
232
34543
4567654
567898765
67890109876
```

If you really want to push things, you can shorten the loops with string concatenation and comprehension, but it's likely harder to read for you.

```
for y in range(1, row_limit):
print()
print((row_limit-y-1) * " " + ''.join([str(x%10) for x in range(y, 2*y)]) + \
''.join([str(x%10) for x in range(2*(y-1), y-1, -1)]), end="")
print()
```

Each of the loops is turned into a list comprehension, such as:

```
[str(x%10) for x in range(y, 2*y)]
```

Then, this list of characters is joined with no interstitial character; this forms half of the row. The second half of the row is the other loop (counting down). In front of all this, I concatenate the proper number of spaces.

Frankly, I prefer my first form.