Python is_prime [closed]

Assume the availability of a function is_prime. Assume a variable n has been associated with positive integer. Write the statements needed to compute the sum of the first n prime numbers. The sum should be associated with the variable total.

Note: is_prime takes an integer as a parameter and returns True if and only if that integer is prime.

So far I have:

i=2
count=0
total=0
while (count<n): if(is_prime(i)): total+=1 count+=1 i+=1

Where am I missing the problem.

1 Answer

to fix your existing ... just add i to total

i=2
count=0
total=0
while (count<n): if(is_prime(i)): total+=i count+=1 i+=1
print total

you could make it much better by making a generator to yield primes forever

def primes(): for i in itertools.count(1): if is_prime(i): yield i

then you could make n_primes that yields the first n primes

def n_primes(n): return [prime for prime,_ in zip(primes(),range(n))]

then lastly you just sum it

print sum(n_primes(N))