Reading Time: 1 minutes
Prime Number or Not in Python: A Python program to check whether the provided number is prime or not.
Prime Number or Not in Python
# PRIME NUMBER OR NOT # The program should contain two functions: one for concluding whether a number is prime or not; the other a main program that reads a number and displays the conclusion. # A prime number is an integer greater than 1 that is only divisible by one and itself e.g. 2, 3, 5, 7, 11, 3, 17, 19 etc. # INPUT: any number # OUTPUT: conclusion if the given number is prime or not # Also, ensure that your file when imported into another file doesn't trigger your program automatically # THOUGHT PROCESS: Construct a function that takes an argument, and returns True or False based on logic -> # Declare a main function(call it anything you want) and have the user input a number -> # Pass the number to the declared function -> # Based on the value returned by the function, display the conclusion -> # include the bit to run the main function if the file has not been imported i.e. it has been run directly. # function to determine whether the supplied number is prime or not. def isPrime(num): if num <= 1: return False for factor in range(2, num): # if there exists any number greater than 2 that if num % factor == 0: # divides the given number evenly(with remainder 0, that is), return False # then the given number is not prime return True # the main function def mainProgram(): number = int(input("Enter the number to be tested: ")) if isPrime(number): print(number, "is prime.") else: print(number, "is not prime.") # if the file has been run directly AND not been imported, call the main function if __name__ == "__main__": mainProgram()
Try it here. You will have to call mainProgram() function yourself, since we have made the script independent by adding the if construct.