In [1]:

    

for num in range(1,101): # for-loop through the numbers
    prime = True # boolean flag to check the number for being prime
    for i in range(2,num): # for-loop to check for "primeness" by checking for divisors other than 1
        if (num%i==0): # logical test for the number having a divisor other than 1 and itself
            prime = False # if there's a divisor, the boolean value gets flipped to False
    if prime: # if prime is still True after going through all numbers from 1 - 100, then it gets printed
        print(num)


    

    




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In [9]:

    

# Modified Code

prime_numbers = list()
for num in range(1,101): # for-loop through the numbers
    prime = True # boolean flag to check the number for being prime
    for i in range(2,num): # for-loop to check for "primeness" by checking for divisors other than 1
        if (num%i==0): # logical test for the number having a divisor other than 1 and itself
            prime = False # if there's a divisor, the boolean value gets flipped to False
    if prime: # if prime is still True after going through all numbers from 1 - 100, then it gets printed
        prime_numbers.append(num)
len_prime = len(prime_numbers) - 1
for i in range(0,len_prime):
    if i % 2 == 0:
        print(prime_numbers[i])


    

    




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In [12]:

    

# Improvement: I am not doing all the calculations for numbers that can be devided by two. 

for num in range(1,101): 
    prime = True 
    if num == 2:
        pass
    elif num % 2 == 0:
        prime = False
    else: 
        for i in range(3,num):
            if (num%i==0): 
                prime = False 
    if prime:
        print(num)


    

    




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