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

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:

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