In this post, We will see how to write a python program for finding prime numbers from the list of numbers in different ways.

Click on this link : Prime Number

Example:

Input:  [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
Output:  Prime Number : -> 2, 3, 5, 7,

Input:  [15, 30, 45, 60]
Output:  No any number from the given list is Prime

Now, Let’s see the codes:

Code 1: Use of for-else python concept. due to this you don’t need to take flag variable.
for-else concept: if for loop run successfully i.e. for loop run completely then else block is not executed otherwise else block is executed.

# Code 1:

# Given number list
numberList = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]

# Empty list
ansList = []

# Iterate through each number 
# form the list
for num in numberList :
    
    # 0 and 1 is not a 
    # prime number
    # so skip this number
    if num == 0 or num == 1 :
        continue
        
    # loop from 2 to half of the
    # given number
    for i in range(2, num // 2 + 1) :

        # If number is divisible by any
        # number (i) then it is not
        # a prime number
        if num % i == 0 :
            break

    # If not divisible then it is
    # a prime number
    else :
        
        # if number is prime
        # then append to the list
        ansList.append(num)

# If list is non-empty then
# print th elements
if len(ansList) :
    
    print("Prime Number : ",end = "-> ")
    
    # printing the prime number
    # from the ansList
    for ans in ansList :
        print(ans, end = ", ")
    
else :
    print("No any number from the given list is Prime")

Output:

Prime Number : -> 2, 3, 5, 7,

Code 2: Make a user defined function for checking number is prime or not.

# define a user defined 
# function for checking
# a number is prime or 
# not
def checkPrime(number) :

    # loop from 2 to half of the
    # given number
    for i in range(2, number // 2 + 1) :

        # if number is divisible by any
        # number (i) then it is not
        # a prime number
        if number % i == 0 :
            return 0

    # if not divisible then it is
    # a prime number
    else :
        return 1
        
# Main code
if __name__ == "__main__" :
    
    # Given number list
    numberList = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
    
    # Empty list
    ansList = []
    
    # Iterate through each number 
    # form the list
    for num in numberList :

        # 0 and 1 is not a 
        # prime number
        # so skip this number
        if num == 0 or num == 1 :
            continue
        
        # function call for checking
        # a number is prime or not
        if checkPrime(num) :
            
            # if number is prime
            # then append to the list
            ansList.append(num)

    # If list is non-empty then
    # print th elements
    if len(ansList) :

        print("Prime Number : ",end = "-> ")

        # printing the prime number
        # from the ansList
        for ans in ansList :
            print(ans, end = ", ")

    else :
        print("No any number from the given list is Prime")

Output:

Prime Number : -> 2, 3, 5, 7,

Code 3: Use of map() and sum() built-in python function.

# Code 3:

# define a user defined 
# function for checking
# a number is prime or 
# not
def checkPrime(number) :
    
    # 0 and 1 is not a 
    # prime number
    # so skip this number
    if number == 0 or number == 1 :
        return 0

    # loop from 2 to half of the
    # given number
    for i in range(2, number // 2 + 1) :

        # if number is divisible by any
        # number (i) then it is not
        # a prime number
        if number % i == 0 :
            return 0

    # if not divisible then it is
    # a prime number
    else :
        # return prime number
        return number
        
# Main code
if __name__ == "__main__" :
    
    # Given number list
    numberList = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10]
    
    # use of map built-in function to call
    # user defined function for all
    # element present in the list
    # and return final list
    ansList = list(map(checkPrime, numberList))

    # if sum of ansList is > 0 that 
    # means it contains prime number 
    # otherwise not
    if sum(ansList) :

        print("Prime Number : ",end = "-> ")

        # printing the prime number
        # from the ansList
        for ans in ansList :
            
            # if ans is non-zero 
            # then print the value
            if ans :
                print(ans, end = ", ")

    else :
        print("No any number from the given list is Prime")

Output:

Prime Number : -> 2, 3, 5, 7,