How to make faster this code

[Ace]

Hello everyone ,
I have occurred in a problem with this code.The thing is that I had to find all prime numbers in a list and delete from list1 all the numbers with divisors !=t ; until that point it's all "ok", but I must find a way to make faster the finding process(for divisors) for numbers like >10000000000

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def findpandd(list1,t):           primes=[]     d={}     for el in list1:         cont=0         r=range(2,el)         for i in r:             if el%i==0:                 cont+=1                 if i>(el**(1/2)) and cont==0:break                 if cont>t:break         d.update({el: cont})     for el in d:         if d[el]==0:primes+=[el]         if d[el]!=t:list1.remove(el)     return list1,primes

[Larz60+]

You have a loop within a loop.
That means that each time the outer loops goes through 1 iteration, the inner loop if executed from start to end.
so in your case, the loop:

1	for i in r:

will run from start to finish from 2 to el for each iteration of list1.
Calculating primes is one place where I would recommend recursion.
see: https://www.daniweb.com/programming/soft...r-function