Please help tweaking this code...primes
Ok, this snippet of code should print 30 prime numbers in ascending order, which it does (code gotten from Borland's Library "Eratosthenes"). BUT it only prints out "1,2,5,7....113" (totally forgets the 3 and the 1 is hardcoded).
if (s==4)
{
RichEdit1->Lines->Insert(0,1);
const int sievesize = 125;
vector<int,allocator<int> > sieve(sievesize, 1);
for (int i = 2; i * i < sievesize; i++)
if (sieve[i])
for (int j = i + i; j < sievesize; j += i)
sieve[j] = 0;
for (int j = 2; j < sievesize; j++)
if (sieve[j])
RichEdit1->Lines->Add(j++);
}
And this snippet of code prints out prime numbers in descending order. BUT it only prints out "113...7,5,3,1" (totally dropping off the 2).
if (s==5)
{
RichEdit1->Lines->Insert(MAX,1);
const int sievesize = 125;
vector<int,allocator<int> > sieve(sievesize, 1);
for (int i = 2; i * i < sievesize; i++)
if (sieve[i])
for (int j = i + i; j < sievesize; j += i)
sieve[j] = 0;
for (int j=sievesize-1; j>0; j--)
if (sieve[j])
RichEdit1->Lines->Add(j--);
}
}
Someone please take a look at this and tell me what I'm missing. Thanks for your help!!!