再探穷举

function(N)
begin
	UP=101
	DOWN=211
	FACTOR=-2
	temp=0
	loop for each decimal digit of N from left to right
	begin // loop
		if digit is equal to 1; add UP to temp
		else if digit is equal to 2; subtract DOWN from temp
		else if digit is equal to 3; multiply temp by FACTOR
	end // loop
	return temp
end