Project Euler Problem 10 - Summation of Primes

main.dart

// Summation of Primes
// https://projecteuler.net/problem=10

void main() {
  final timer = Stopwatch()..start();

  final answer = summationOfPrimesBelow(2000000);
  
  timer.stop();

  print('\nProject Euler #10\nAnswer: $answer');
  print('Elapsed time: ${timer.elapsedMilliseconds} milliseconds.\n');
}


int summationOfPrimesBelow(int limit) {
  int sum = 0;

  for (int prime in primeGenerator().takeWhile((prime) => prime < 2000000)) {
    sum += prime;
  }
  
  return sum;
}

Iterable<int> primeGenerator() sync* {
  yield 2;
  yield 3;

  var number = 3;
  while (true) {
    number += 2;

    var isPrime = true;
    for (var i = 2; i * i <= number; i++) {
      if (number % i == 0) {
        isPrime = false;
        break;
      }
    }

    if (isPrime) {
      yield number;
    }
  }
}