I can't seem to pass the <> test. The output looks identical to the test, but says that it doesn't pass. Here is the code:

acount, bcount = [int(i) for i in input().split(' ')]
aset, bset, cset = set(), set(), set()
for a in range(acount):
    aset.add(int(input()))
for b in range(bcount):
    bset.add(int(input()))
print(len(aset & bset))
for c in aset & bset:
    print(c)
print(len(aset - bset))
for a in aset - bset:
    print(a)
print(len(bset - aset))
for b in bset - aset:
    print(b)    

Heres the produced output, that looks just like the test case:

2
0
1
2
9
10
1
3

Did I miss something in the test? All but the first one pass.

Hi, The last sentence of this page https://snakify.org/en/lessons/dictionaries_dicts/ is as follows,
"To loop through keys and variables, you can do the following"
But it should be,
"To loop through keys and values, you can do the following"

Thank you.

@vpavlenko As I have been working the problems, I am noticing a variety of ways to structure the problem statements. I think it might be beneficial to create a simple standard that is followed, and then every update should approach the standard. One possible start:

Consistent order:

1. Given (use input())
2. Goal/objective for the code
3. Output (use print())
4. Restrictions/Don't use

Use of Math structures:

• Favor the problem written in simple English phrases.
• Mark declared variables as math symbols
• Use mathematics expressions when the English will be complicated or confusing or really long.

What do you think?

3.4 should say "Given a positive integer".
4.3 should say "10 integers" not 10 numbers.
5.2 advises the student to use count. The simplest answer, counting the number of space characters, fails if there are multiple consecutive space characters in the input. The model solution is superior, but does not use count.
6.3 should say "For a given positive integer"... there is no solution if X < 1.
6.8 The model solution would be less confusing if line 4 was 'if a > maximum'; a student would wonder why >= is necessary (it isn't).
6.9 I had two issues with this. I was not sure where "first maximum" meant a relative (local) maximum (such as 2 in the sequence 2,1,3,2,3,0) or the first appearance of the absolute maximum value for the entire sequence (such as the 3 that follows the 1). Also, the example and the model solution use 1-based indexing, and that was not immediately clear. At first I assumed that "index" referred to the more-usual Python 0-based indexing convention.
6.B It was not immediately clear to me that "greater than their neighbors above" meant greater than their immediately preceding element. I was unsure about how many "neighbors above" to consider for each element. I know this seems silly in retrospect, but that was my reaction.
6.C Another probably silly problem. The statement that the sequence ends with 0 allows the possibility that 0 is part of the sequence, in which case (1,0) satisfies the guarantee of a sequence of at least two elements. Perhaps stating "not including the 0" would avoid any initial confusion.

First time through I couldn't find this for ages. My first bunch of students had the same trouble.

If all the tests have passed the 'Next problem' should be a giant (green?) button. Or something.

Issue

It appears that there might be issues within the Problem section in terms of the Input and possibly output windows. The possible issue comes from the students understanding what each line of the input and output represent...as not everyone is fluent in English.

Solution

Provide a mechanism for each problem set that indicates what each input and output represents. Or at the very least those problem sets that might cause a student to pause or stop their train of thought.

Idea 1

Expand the Problem Statement to more clearly indicate what each input and output represents. This appears to be the easiest solution; however, it pushes the code window down farther and is more text to read.

Idea 2

Create a new section that displays when the user hovers over a question-mark like icon near the input and output windows. This is more work to implement but can provide a clearer indication of what each input and output are.

Idea 3

Allow for displaying the input and comment-like representation in the input and output windows. At least for the Tests. There are no extra displays to implement, but it would require reworking the internals I believe.

Next to the Run Test #1 button, instead of it displaying

Input:

1
1
1
2
2
2

Output:

3661

It would display the something like the following...

Input:

1    # hour - time 1
1    # minute - time 1
1    # second - time 1
2    # hour - time 2
2    # minute - time 2
2    # second - time 2

Output:

3661    # difference in seconds

Example

If you look at the input for the Two Timestamps Problem Set that is part of the subscription in Lesson 1. There are 6 unlabeled inputs and 1 unlabeled output. By reading the problem statement, you should be able to figure out what each input means, but some problems that are harder than others.

New students might think it is second1, minute1, hour1, second2, minute2, hour2 (That seems reasonable). Or they might think it is hour1, hour2, minute1, minute2, second1, or maybe something else.

Side Note

This could also allow students to create better variable names. Again, not everyone is fluent in English and pulling out the correct information from an English sentence can be hard sometimes.

Holding an exam makes teachers able to check students' progresses.

The problem here states:

H hours, M minutes and S seconds are passed since the midnight (0 ≤ H < 12, 0 ≤ M < 60, 0 ≤ S < 60). Determine the angle (in degrees) of the hour hand on the clock face right now.

However, tests don't actually expect the answer in degrees, they expect the answer in decimal minutes and seconds. Happy to provide a PR to fix this either way, but I just want to clarify before I do that you don't actually mean degrees?

--

If you mean degrees, then the following logic would hold true:

15 minutes = 90 degrees
30 minutes = 180 degrees
45 minutes = 270 degrees
60/0 minutes = 360/0 degrees

Such that:
1 minute = 6 degrees

Resulting in:
30 seconds = 3 degrees
10 seconds = 1 degree
1 second = 0.1 degree

The resulting code would be:

h = int(input())
m = int(input())
s = int(input())

print((m * 6) + (s * 0.1))

--

If you mean the decimal minutes and seconds, then the current tests are correct but I'll need to update the language within the question.

If you could clarify @vpavlenko / @goldvitaly, I'll happily PR this.

Can the checking engine be tweaked to look for solutions anywhere in the output?

I've had two students email me unable to complete step 10 of 'Integers and floats', even though their code is correct, because the checker requires you to delete your solution to step 1 and replace it with the solutions to step 2.

In the input, print and number group of problems - the individual tasks appear in an order that is not necessarily helpful to the student. For example:
Hello, Harry! and Previous and next appear after the hard task Digital clock. https://snakify.org/lessons/print_input_numbers/problems/

Is there a way to either identify a task as E/M/H or to have them appear in ascending difficulty order?

When you scroll down to see the tests, it would be helpful to see the output from your program next to the Correct output. My student was doing the area of a right triangle exercise but didn't divide by 2. He saw the Correct answer was 7.5 but couldn't see that HIS answer was 15 (which would've clued him in to the solution).

BTW This is my first time using github for anything real, so apologies if I'm "doing it wrong". I've been a coder for 38 years (now a CS teacher in Cambodia) but back when I was coding commercially it was cvs - and not much of that!

The goal is to make slow-pacing students busy and studying, so not to have them struggle on hard problems without any success. Please, share your task ideas below.

This is the common standard on many 'Learn to code' sites (such as codewars).

what is the code for this question?