[Python] Fastest Method for Find Multiplication Array ( by Minimum Number of Operations)

An interview question:

I have an array: for example this one:

a,b,c,d,e,f,g!=0

List_1=[a,b,c,d,e,f,g]


and I wan to find an optimum method with least operators to find this result:

Multiplication=[a+bcdefg,ab+cdefg,abc+defg,abcd+efg,abcde+fg,abcdef+g]


I propose to use this method:

mult=a*b*c*d*e*f*g
Multiplication=[]
Temp=List_1[0]
while(i<(len(List_1))-1):
mult/=List_1
Multiplication.append(Temp+mult)
Temp*=List_1[i+1]


This line mult=a*b*c*d*e*f*g take n-1 multiplication, while loop take n-1 multiplication, n-1 division and n-1 addition. So overall time is approximately 3n-3 multiplication and n-1 addition.

Is this simplest method or there are other methods with minimum memory and time?

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