Project Euler #10 Java not working -


the sum of primes below 10 2 + 3 + 5 + 7 = 17.

find sum of primes below 2 million.

            public class problem10             {                 public static void main(string[] args)                 {                     int sum = 17;                     for(long i=11; i<2000000; i+=2)                     {                         if(isprime(i)) sum += i;                     }                     system.out.println(sum);                      }                  public static boolean isprime(long n)                 {                     if(n==2) return true;                     if(n%2 == 0) return false;                     for(long i=3; i<= math.sqrt(n); i+=2)                     {                         if(n%i == 0) return false;                     }                     return true;                 }             }

i don't see wrong this. keeps printing 1179908154 incorrect.

your sum int, integer overflow occurring. if change datatype long, answer changes 142913828922, longer maximum possible int. that appears correct answer.


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