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Python Exercise: Test the number is prime or not

Python Functions: Exercise-9 with Solution

Write a Python function that takes a number as a parameter and check the number is prime or not.

Note : A prime number (or a prime) is a natural number greater than 1 and that has no positive divisors other than 1 and itself.

Prime Number

Prime number between 1 to 100:

Prime Number between 1 to 100

Sample Solution-1:

Python Code:

def test_prime(n):
    if (n==1):
        return False
    elif (n==2):
        return True;
    else:
        for x in range(2,n):
            if(n % x==0):
                return False
        return True             
print(test_prime(9))

Sample Output:

False

Flowchart:

Flowchart: Python exercises: Test the number is prime or not.

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:


Sample Solution-2:

  • Return False if the number is 0, 1, a negative number or a multiple of 2.
  • Use all() and range() to check numbers from 3 to the square root of the given number.
  • Return True if none divides the given number, False otherwise.

Python Code:

from math import sqrt
def is_prime(num):
  if num <= 1 or (num % 2 == 0 and num > 2): 
    return False
  return all(num % i for i in range(3, int(sqrt(num)) + 1, 2))
print(is_prime(11))
print(is_prime(13))
print(is_prime(16))
print(is_prime(17))
print(is_prime(97))

Sample Output:

True
True
False
True
True

Flowchart:

Flowchart: Python exercises: Test the number is prime or not.

Visualize Python code execution:

The following tool visualize what the computer is doing step-by-step as it executes the said program:


Python Code Editor:

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Previous: Write a Python function that takes a list and returns a new list with unique elements of the first list.
Next: Write a Python program to print the even numbers from a given list.

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Python: Tips of the Day

Decapitalizes the first letter of a string:

Example:

def tips_decapitalize(s, upper_rest=False):
  return s[:1].lower() + (s[1:].upper() if upper_rest else s[1:])
print(tips_decapitalize('PythonTips'))
print(tips_decapitalize('PythonTips', True)) 

Output:

pythonTips
pYTHONTIPS