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POSyntax error? Ruby bug? Issue with instance variable incrementing with += 1?
 

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    <pre><code>def isPrime?(num) i = 2 @isFalse = 0 while i &lt; num divisible = ((num % i) == 0) if divisible @isFalse += 1 return false end i += 1 end true end def primes(max) startTime = Time.now (2..max).each do |p| puts "#{p} #{isPrime?(p)}" end endTime = Time.now puts "--------------------------------------------------" puts " FALSE values in range from (2 thru #{max}): #{@isFalse} \n TRUE values in range from (2 thru #{max}): #{max-1-@isFalse}" puts "\nTotal time to calculate is #{endTime - startTime} seconds!" end primes(10) </code></pre> <p><code>isPrime?</code> checks if a given number is a prime number. <code>primes</code> loads a range of numbers and checks if each is a prime.</p> <p>I want to know how many numbers are prime within the range and how many aren't.</p> <p>I added <code>@isFalse += 1</code> thinking I can increment each time false is returned so that I can determine how many numbers in the range are false and use this to subtract from <code>max</code> to get how many numbers are true.</p> <p>Entire code is working correctly except <code>@isFalse</code> is not properly incrementing. Why is that? Thanks for the help.</p> <p><strong>--UPDATE--</strong><br> My Output: added <code>puts "About to increment @isFalse"</code> before <code>@isFalse += 1</code></p> <pre><code>2 true 3 true About to increment @isFalse 4 false 5 true About to increment @isFalse 6 false 7 true About to increment @isFalse 8 false About to increment @isFalse 9 false About to increment @isFalse 10 false -------------------------------------------------- FALSE values in range from (2 thru 10): 1 TRUE values in range from (2 thru 10): 8 </code></pre>
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    1. COQuick debugging check: print something before the `@isFalse += 1` line (eg, `puts "About to increment @isFalse"`). This should help pinpoint the problem.
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    2. COFollowing your suggestion does in fact output the string 5 times `puts "About to increment @isFalse"`
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    3. CO@alecbenzer any other suggestion? I am stumped here.
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