$35
COSC 326
Red and green
In many computer languages (including e.g, Java) division of positive integers is performed by truncating the “correct” answer, so that for instance 13 divided by 3 produces
the result 4 (I just can’t bring myself to write 13/3 = 4.) Given a positive integer n let us
say that an integer k is a near factor of n, if there is some 2 ≤ d ≤ n such that n divided
by d produces the result k. For instance, the near factors of 13 are:
1, 2, 3, 4, 6.
The positive integers are going to be divided into two groups, called green and red,
according to the following rules:
• 1 is green.
• A positive integer n > 1, n is red if more of its near factors are green than are red.
Otherwise, it is green.
For instance:
n Near factors Type
1 Green
2 1 Red
3 1 Red
4 1, 2 Green
5 1, 2 Green
6 1, 2, 3 Green
7 1, 2, 3 Green
8 1, 2, 4 Red
Task
Input from stdin will consist of a series of lines each of which is (supposed to be) a
scenario. A scenario consists of a pair of positive integers, a and b (separated by a space)
with a ⩽ b. The output for a correctly formatted scenario is: a b <colours> where
<colours> is a string consisting of the characters R and G representing the types of
the integers a through b inclusive. If input is incorrectly formatted in any way then
the output for that line should be Bad input: <in> where <in> is a copy of the
input.
You may assume that b will be at most ten million.
(1 point, Individual)