22 lines
700 B
Python
22 lines
700 B
Python
#Generate the largest prime number smaller than a given natural number n. If such a number does not exist, a message should be displayed.
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def is_prime(n):
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if n<2:
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return False
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for i in range(2,round(n**0.5)+1):
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if n%i==0:
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return False
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return True
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def largest_prime_number_smaller_than_n(n):
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if n < 3:
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print("No such number exists")
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return None
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for i in range(n-1,0,-1):
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if is_prime(i):
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print("The smallest prime number smaller than {} is {}".format(n,i))
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return i
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if __name__=="__main__":
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n=int(input("Please enter an positive integer number: "))
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largest_prime_number_smaller_than_n(n) |