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Python: Sieve of Eratosthenes method, for computing prime number

Python List: Exercise - 34 with Solution

Write a Python program that uses the Sieve of Eratosthenes method to compute prime numbers up to a specified number.

Note: In mathematics, the sieve of Eratosthenes (Ancient Greek: κόσκινον Ἐρατοσθένους, kóskinon Eratosthénous), one of a number of prime number sieves, is a simple, ancient algorithm for finding all prime numbers up to any given limit.

Python: Sieve of Eratosthenes method, for computing prime number

From Wikipedia Sieve of Eratosthenes: algorithm steps for primes below 121 (including optimization of starting from prime's square).

Sample Solution:-

Python Code:

def prime_eratosthenes(n):
    prime_list = []
    for i in range(2, n+1):
        if i not in prime_list:
            print (i)
            for j in range(i*i, n+1, i):
                prime_list.append(j)

print(prime_eratosthenes(100));

Sample Output:

2                                                                                                             
3                                                                                                             
5                                                                                                             
7                                                                                                             
11                                                                                                            
-------
79                                                                                                            
83                                                                                                            
89                                                                                                            
97                                                                                                            
None   

Flowchart:

Flowchart: Sieve of Eratosthenes method, for computing prime numbers

Python Code Editor:

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Python: Tips of the Day

Creates a list of elements, grouped based on the position in the original lists:

Example:

def tips_zip(*args, fill_value=None):
  	max_length = max([len(lst) for lst in args])
 	 result = []
  	for i in range(max_length):
   	 result.append([
      args[k][i] if i < len(args[k]) else fillvalue for k in range(len(args))
   	 ])
 	 return result
print(tips_zip(['a', 'b'], [1, 2], [True, False]))
print(tips_zip(['a'], [1, 2], [True, False]))
print(tips_zip(['a'], [1, 2], [True, False], fill_value = '1'))

Output:

[['a', 1, True], ['b', 2, False]]
[['a', 1, True], [None, 2, False]]
[['a', 1, True], ['1', 2, False]]