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https://github.com/TheAlgorithms/Ruby
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34 lines
742 B
Ruby
34 lines
742 B
Ruby
# A ruby program to check a given number is prime or not
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# Mathematical explanation: A number which has only 2 factors i.e., 1 (one) and itself
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# Prime number check function
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def prime_number(number)
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if number <= 1
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non_prime_flag = true
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elsif number == 2
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non_prime_flag = false
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elsif number % 2 == 0
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non_prime_flag = true
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else
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non_prime_flag = (2..Math.sqrt(number)).any? { |i| number % i == 0 }
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end
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if !non_prime_flag
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puts "The given number #{number} is a Prime."
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else
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puts "The given number #{number} is not a Prime."
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end
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end
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# Non-prime input
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prime_number(1)
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# prime input
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# Number 2 is an even prime number
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prime_number(2)
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# Non-prime input
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prime_number(20)
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# Negative input
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prime_number(-21)
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