Updated: Finding the least common multiple of a list of numbers in python

Question

Hi I have updated this with my code:

Input ->

a=[16,21, 56, 40]

def find_primes(a):
    num_factors=[] 
    for num in a:
       # print('1',num)
        list_of_factors=[]
        i=2
        while num>1:
            #print('2',num)
            if num%i==0:
                list_of_factors.append(i)
               # print('3',list_of_factors)
                num=num/i
               # print('4',num)
                i=i-1
                
            i+=1 
        num_factors.append(list_of_factors)  
    d = {}
    a_list = []
    for i in num_factors:
        for j in i:
            d[j] = d.get(j, 0) + 1
            dictionary_copy = d.copy()
    a_list.append(dictionary_copy)  
    print(a_list)
    return num_factors
    
find_primes(a)

This is the output I am getting:

[{2: 10, 3: 1, 7: 2, 5: 1}]
[[2, 2, 2, 2], [3, 7], [2, 2, 2, 7], [2, 2, 2, 5]]

Here is my question:

Understand since it is a dictionary, the value for the key accumulates.

I want to have the count of unique integers from each list. For eg. [{2:4},{3:1,7:1},{2:3,7:1},{2:3,5:1}] instead of what is given in the output from the code above.

After which, I want to get the max occurrence for each of the integers to calculate the LCM. 2^4 * 3 * 7 * 5

Kindly advise on how we could improve on the code. Appreciate the help.

Answer 1

This could be one of the approach.

numbers=list(map(int,input().split()))
numbers.sort()
maximum=numbers[0]  #gcd of the input numbers cannot be greater than minimum number in the list.Therefore we are retrieving the mininum number of the list.
    gcd=1               #Initial value of gcd.
    for i in range(1,(maximum+1)):
        flag=0
        for j in range(len(numbers)):
            num=numbers[j]
            if num % i ==0:      #check if the every number in the input is divisible by the value of i
                 flag=1          #if divisible set flag=1 and then check the other numbers of the input.
            else:
                 flag=0          #if any of the number of the input is not divisible then flag =0 and go to next iteration of i.
                 break
        if flag==1:
            gcd=i         #if flag=1 that means every number of the input is divisible by the value of j.Update the value of gcd.
    
    print(gcd)

That can be done in the following way:

for i in num_factors:
    d={}
    for j in i:
       
            try:
             d[j]=d[j]+1
            except KeyError:
             d[j]=1

    dictionary_copy = d.copy()
    a_list.append(dictionary_copy)  
print(a_list)
return num_factors