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/*
* Read n from stdin and print all primes from 1 to n to stdout.
* This is free and unencumbered software released into the public domain.
*/
#include <stdio.h>
#include <stdlib.h>
void subsieve(int *mask, int n, int i, int j)
{
if (j > n)
return;
mask[j] = 1;
subsieve(mask, n, i, i + j);
}
void sieve(int *mask, int n, int i)
{
if (i * i > n)
return;
if (!mask[i])
subsieve(mask, n, i, i + i);
sieve(mask, n, i + 1);
}
void print_primes(int *mask, int n)
{
if (!n)
return;
if (!mask[n])
printf("%d\n", n);
print_primes(mask, n - 1);
}
int main()
{
int n;
scanf("%d", &n);
int *notprime = calloc(n + 1, sizeof(int));
notprime[0] = notprime[1] = 1;
sieve(notprime, n, 2);
print_primes(notprime, n);
return 0;
}
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