#include <stdio.h>

#define N 10000000
#define MY_TRUE 1
#define MY_FALSE 0

void printTab(char *tab, int n)
{
    int i;
    for (i = 0 ; i < n ; i++)
        {
            if (tab[i] == MY_TRUE)
                printf("%d ", i);
        }
    puts("");
}

int main()
{
    char tab[N] = {0};
    int i, j;

    for (i = 0 ; i <= N ; i++)
        {
            tab[i] = MY_TRUE;
        }

        tab[0] = tab[1] = MY_FALSE;

        i = 2;
        while (i <= N)
            {
                j = i*2;
                while (j <= N)
                    {
                        tab[j] = MY_FALSE;
                        j += i;
                    }
                i++;
                while (i <= N && tab[i] == MY_FALSE)
                    i++;
            }

    //printTab(tab, N);

    return 0;
}