Loop question, I've tried everything that I knew I just don't know. Please help me solve it out

Question

How to I make a code that gives you how many are same in a list, using a loop, for example:
Num = [1, 3, 2, 5, 7, 8, 7, 3, 1, 1]
And it returns:
1 = 3
2 = 1
3 = 3
5 = 1
7= 2
8 = 1

Answer 1

svnshqinz ,

here is a very basic approach without dictionary

> since numbers can occur multiple times in the input values, we have to take care that only the first occurrence of each
value is counted. to do so, we need a helpers list *already_seen*, where we can append numbers that have been already
counted.

> we start a for loop, that gets one number at a time from the input list and is stored in a loop variable variable like *num*

> inside the loop, we check if the current number is NOT already seen. this can be done with an *if* conditional and using
the *in* operator.

> if the current number is not in *already_seen*, we can output the result with print(...)
to get the count of the specific number, we can use the string.method count(...) like:

... nums.count(num)

> after this, we have to append the current number (variable *num*) to list *already_seen*

> if the loop is terminated, all numbers with the counts have been printed

Answer 2

another thing i wanted to mention:

it is not seen as very helpful when we are going to post a ready-made code, as long as the op has not shown his attempt here.

it is more helpful to give hints and tips, so that the op has a chance to find a solution by himself.

Answer 3

Should the output be in sorted form like that 1 = 3 ... 8 = 1?

Answer 4

svnshqinz

Create a set from <Num> list to get only unique elements name it <num_set>

Then create a list named <sorted_num> from <num_set> and sort the list

Next, create a dictionary named <num_freq> where each item key is the value obtained from <sorted_num>, and item value is the frequency of the value in <Num> list.

Lastly, display the numbers and their frequency you have collected in <num_freq> dictionary

You can try this for now, or ask others how their code example work : )

Answer 5

Ipang yes

Answer 6

Ipang thank you! Actually it didnt need to be sorted but I was to distracted and didn't notice :)

Answer 7

Num = [1, 3, 2, 5, 7, 8, 7, 3, 1, 1]

print(*[f'{n} = {Num.count(n)}' for n in sorted(set(Num))],sep='\n')

Answer 8

Lothar, ok thank you very much :)