Problem Statement

Ethiopian multiplication is a method of multiplying integers using only addition, doubling, and halving.

Method:

For example:   17 × 34 Halving the first column: Doubling the second column: Strike-out rows whose first cell is even: Sum the remaining numbers in the right-hand column: So 17 multiplied by 34, by the Ethiopian method is 578.

The task is to define three named functions/methods/procedures/subroutines:

Use these functions to create a function that does Ethiopian multiplication.

Let's start with the solution:

function half(x)
set result = floor(x/2)
end function

function double(x)
set result = 2*x
end function

function even(x)
set result = (x/2 > floor(x/2))
end function

program ethiopian_mul(a,b)
relation first, second
while a >= 1
insert a, b
set a = half(a)
set b = double(b)
end while
extend third = even(first) *  second
project third sum
end program

run ethiopian_mul(17,34)
print