Solution Exercise 754: algorithm python to find the smallest prim number

Exercise 754

Write a Python algorithm as a function that takes an integer n as argument and returns the smallest prime integer greater than or equal to n. Example for n = 8, the function returns the smallest prime number greater than or equal to 8 which is 11.

Solution

# creating function to test if given number is prim or not
def testPrim(m):
    # Initializing number of divisors
    numberDivisors = 0
    
    # while i is divisor of m we increment numberDivisors
    for i in range(1 , m + 1):
        if(m%i == 0):
            numberDivisors = numberDivisors + 1
            
    # a number is prime if and only if it has two divisors, 1 and itself
    if (numberDivisors == 2):
        return True
    else:
        return False
    
def smallestPrim(n):
    # initializing value of searched smallest prim p
    p = n
    while ( not testPrim(p) ):
        p = p + 1
    return p
# Testing algorithm
print("The smallest prim greater than or equal 18 is : " , smallestPrim(18))
# The output is : The smallest prim greater than or equal 18 is :  19