Kata

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

You will be given the lower and upper limits: the program will look for any prime number that exists between the lower limit to the upper limit (included).

Your objective is to sum all the primes between the given limits.

• If the limits are primes, then they are included
• -100000 <= lower < upper <= 100000
• If lower is greater than upper, it should return 0

Example

You are given a lower limit of 4 and an upper limit of 20.

So the prime numbers from 4 to 20 will be: 5, 7, 11, 13, 17, 19

and if you add them up, the result will be 72.

sum_primes(4, 20) = 72  # 5 + 7 + 11 + 13 + 17 + 19 = 72

sum_primes(20, 4) = 0  # since lower is greater than upper

sum_primes(2, 7) = 17  # 2 + 3 + 5 + 7 = 17

sum_primes(11, 11) = 11  # it consists of one prime number

sum_primes(60, 60) = 0  # since 60 is not a prime number