21 lines
596 B
Python
21 lines
596 B
Python
"""This program prints all prime numbers over a specified interval"""
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x, y = 2, 100 # defining the range
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# create a boolean list to mark primes, assume all are prime initially
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primes = [True] * (y + 1)
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# 0 and 1 are not prime
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primes[0], primes[1] = False, False
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# Sieve of Eratosthenes to mark non-primes
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for i in range(2, int(y ** 0.5) + 1):
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if primes[i]:
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for j in range(i * i, y + 1, i):
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primes[j] = False
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# collect primes in the range [x, y]
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res = [i for i in range(x, y + 1) if primes[i]]
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print(res if res else "No")
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print ("the number of primes is: ", len(res))
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