Originally Posted by wolfrose

In the first code the loop counter which is cnt2 and assigned by cnt1
In the second code the loop counter is cnt1 and assigned by cnt

I have three variables in both codes

So In the first code decrementing

Code:

The first code: cnt2=$(($cnt2 - 1))

is before the main arithmetic expression

Code:

The first code: cnt1=$(($cnt1 * ($cnt2)))

In the second code I want to combine decrementing and main expressions in one arithmetic expression

Code:

The second code: cnt=$(($cnt * ($cnt1 - 1)))

The part on the right of the second expression should do the same operation as in the decrementing line of the first code; I think they are the same.

---------- Post updated at 03:38 AM ---------- Previous update was at 01:41 AM ----------

OK I got it!!

You're right the internal variable cnt1 is not assigned to be updated, so I read in a website about assigning variables.

Code:

ead -p "Enter number: " n
  2 
  3 cnt=$n
  4 cnt1=$cnt
  5 while [ $cnt1 -gt 1 ]
  6 do
  7 cnt=$(((cnt * (cnt1 -= 1 ))))
  8 done
  9 
 10 echo result= $cnt cnt1=$cnt1

This is the result to get the correct answer.

Thank you,