Python prime number generator using generators

Python: Generators Yield Exercise-3 with Solution

Write a Python program that creates a generator function that generates all prime numbers between two given numbers.

A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways of writing it as a product, 1 × 5 or 5 × 1.

Sample Solution:

Python Code:

def is_prime(n):
    if n <= 1:
        return False
    for i in range(2, int(n**0.5) + 1):
        if n % i == 0:
            return False
    return True

def prime_nums_generator():
    n = 2
    while True:
        if is_prime(n):
            yield n
        n += 1

# Create the generator object
primes = prime_nums_generator()

# Accept input from the user
n = int(input("Input the number of prime numbers you want to generate? "))

# Generate and print the first 10 prime numbers
print("First",n,"Prime numbers:")
for _ in range(n):
    print(next(primes))

Sample Output:

Input the number of prime numbers you want to generate? 12
First 12 Prime numbers:
2
3
5
7
11
13
17
19
23
29
31
37

Explanation:

In the above exercise,

• The is_prime(n) function checks whether a number n is prime.
• The prime_nums_generator() function is a generator. It initializes n to 2, the first prime number, and enters an infinite loop. It checks if n is prime using the is_prime() function, and if so, it yields n. Then, it increments n by 1 and continues the loop.
• The generator object primes is created by calling the prime_nums_generator() function.
• The program prompts the user to input the number of prime numbers they wish to generate and stores it in the variable n.
• The program then iterates over the generator using a for loop. In this case, it generates and prints the specified number of prime numbers by calling next(primes).

Flowchart:

Python Code Editor:

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