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Statement

 Goal

You have to multiply two integers (a&b) by means of a method used in Ancien Egypt, described in Rhind’s hieratic papyrus written circa −1650 by Ahmes. This method is still used in Russia.

First, sort the two numbers.
Then follow the steps below, the algorithm uses base-2 decomposition of the biggest number.
We multiply 12 by 5, here is what you have to print, excepted the comments after hashes.

12 * 5
= 12 * 4 + 12 # Divide 5 by 2, the remain is 1 and 5=2×2+1, thus 12*5=12*(2*2+1)=12*2*2+12=24*2+12
= 24 * 2 + 12 # Divide 2 by 2, 2=1*2+0 and 12*5=24*(1*2+0)+12=48*1+12
= 48 * 1 + 12 # Divide 1 by 2, 1=0*2+1 and 12*5=48*(0*2+1)+12=12+48
= 48 * 0 + 12 + 48 # End of the algorithm
= 60
Input
Two integers separated by a space.
Output
The description of the successive operations.
Constraints
0<= a, b <= 32768
Example
Input
3 12
Output
12 * 3
= 12 * 2 + 12
= 24 * 1 + 12
= 24 * 0 + 12 + 24
= 36
Solve it

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