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#include <fits.h>
#define result (rv.i4data)
Fits &primes(int k, Fits &rv) {
rv.create(k, 1, I4);
if (k == 1) {
result[0] = 2;
return rv;
}
result[0] = 2;
unsigned long n = 3;
unsigned long count = 1;
result[count] = 3;
count++;
while(count < k) {
n = n + 2;
for (int ip = 1; ip < count; ip++) {
double q = n / result[ip];
int r = n % result[ip];
if (r == 0) {
ip = count + 1; // n is not prime.
} else {
if (q <= result[ip]) { // n is prime.
result[count] = n;
count++; // compute next prime.
ip = count + 1;
}
}
}
}
return rv;
}
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