Multiply digits within a number with each other

Question

I have list of numbers, and I want to multiply the digits within each number with each other; e.g. for the number 1234 it is 1 X 2 X 3 X 4 = 24

E.g. the following input

7675342567 098765342567 1234567890 0987654 234567 8765678 98 0999 09876543 345678 876543 87654

needs the following result:

7408800 0 0 0 5040 564480 72 0 0 20160 20160 6720

How should I proceed?

Sorry but this is not a scripting service. If you do not know any shell scripting, you'd start learning. — andcoz
– andcoz, Commented Oct 8, 2018 at 15:39
@andcoz i don't like programming and it is not my hobby, I have problem and I need help what is wrong with that? — Sydney
– Sydney, Commented Oct 8, 2018 at 15:40
Sydney: The problem is that this site teaches people programming. If you don't care about the "how", pay someone to solve the problem for you. — choroba
– choroba, Commented Oct 8, 2018 at 15:50
"what is wrong with that?" is a complex question, please read this: How do you feel about “GIVE ME TEH CODEZ” questions? — andcoz
– andcoz, Commented Oct 8, 2018 at 15:52

Stéphane Chazelas · Accepted Answer · 2018-10-08 15:47:15Z

You can do it this way:

<file sed 's/./&*/g;s/*$//' | bc 7408800 0 0 0 5040 564480 72 0 0 20160 20160 6720

With GNU sed, that can be simplified as:

<file sed 's/./*&/2g' | bc

Jeff Schaller · Accepted Answer · 2018-10-09 00:58:30Z

Strictly within bash, assuming you don't overflow beyond 9 quintillion and change (9,223,372,036,854,775,807),

while IFS= read -r do res=1 for((i=0;i<${#REPLY};i++)) do res=$((res * ${REPLY:i:1})) done echo "$res" done < input > output

2 Answers 2