I've check to see if the program is recieving number and names and it is. I'm wondering why doesn't it print "fred" when input number is 1?
number = ARGF.read.chomp
names = %w{fred betty barney}
if number == 1
puts names[0]
elsif number == 2
puts names[1]
elsif number == 3
puts name[2]
end
number is likely a string here, but you are comparing it with an integer.
1 == '1' # false
try
number = ARGF.read.chomp.to_i # note the to_i here
names = %w{fred betty barney}
if number == 1
puts names[0]
elsif number == 2
puts names[1]
elsif number == 3
puts names[2]
end
Also, you can use a case/when statement when you want to take a different path based on multiple values of a single variable. This is usually the cleaner way to handle this type of flow.
number = ARGF.read.chomp.to_i
names = %w{fred betty barney}
case number
when 1
puts names[0]
when 2
puts names[1]
when 3
puts names[2]
end
Or in this case, the even more simple:
number = ARGF.read.chomp.to_i
names = %w{fred betty barney}
puts names[number-1]
should work.
case statement is better for a number of reasons: It's significantly faster to execute, it is easier to read especially when mapping several values to a singular action as no or is required, and it's impossible to inadvertently assign with = instead of comparing with ==. You're also, worryingly, the only answer that recognized this is an array indexing problem and doesn't need that kind of logic at all.
I know you're learning if...else, but keep in mind you can also do this:
number = ARGF.read.chomp.to_i - 1
names = %w{fred betty barney}
puts names[number]
number is a string, not an integer. You can either convert to an integer:
number = ARGF.read.chomp.to_i
or you can test against strings instead:
if number == "1"
...
...
...
The number is a string. You can check that that by printing its class like this:
p number.class
You need to convert number to an integer like this:
number = ARGF.read.chomp.to_i
Keep in mind though that to_i would return 0 for invalid string. Do it only when you are sure about the incoming data.
Try this on Codepad.
