Project Euler #10 (Python)

Question

Why is my algorithm for finding the sum of all prime numbers below 2 million so slow? I\'m a fairly beginner programmer and this is what I came up with for finding the solution:

Answer 1

You need to use prime sieve check out eratostheneses sieve and try to implement it in code.

Trial division is very inefficient for finding primes because it has complexity n square, the running time grows very fast. This task is meant to teach you how to find something better.