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#include <stdlib.h>
#include <stdio.h>
#include <stdint.h>
#include <unistd.h>
#include <string.h>
int main(int argc, char **argv)
{
int opt;
const char *optstr = "n:";
long count = -1;
int current, i, primecount = 0;
while ((opt = getopt(argc, argv, optstr)) != -1)
{
switch (opt)
{
case 'n':
count = strtol(optarg, NULL, 0);
break;
case '?':
exit(1);
}
}
if (count <= 0)
{
exit(1);
}
char *sieve = malloc(sizeof(char) * count);
memset(sieve, 1, sizeof(char) * count);
current = 2;
while (current < count)
{
if (sieve[current])
{
primecount++;
for (i = current*2; i < count; i+=current)
{
sieve[i] = 0;
}
}
current++;
}
printf("const long prime_table[%d] = { 2", primecount);
for (i = 3; i < count; ++i)
{
if (sieve[i])
{
printf(",%d", i);
}
}
printf("\n};\n");
printf("const long prime_table_size = %d;\n", primecount);
free(sieve);
return 0;
}
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