150113_CribaErastotenes, C (gcc)

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//Title of this code
//gcc 4.8.2

#include  <stdio.h>
#include <math.h>

short asignarPrimosAlArray(long d, long a[d]);
void mostrarArray(long d, long a[d]);
void cribaErastotenes(long d, char c[d]);

#define _D 100000

int main(void)
{
    long primos[_D];
    short valorRespuesta = asignarPrimosAlArray(_D, primos);
    if(valorRespuesta == 0)
    {
        mostrarArray(_D, primos);
    }
    else
    {
        printf("Agh!!!!!: No tengo suficientes primos...\n");
    }
    
    
    return 0;
}

short asignarPrimosAlArray(long d, long a[d])
{
    long dim = 1000000;
    long i, j;
    char erastotenes[dim];
    cribaErastotenes(dim, erastotenes);
    for(i = 1 , j = 0 ; j < d && i < dim ;i++)
    {
        if(erastotenes[i] == 'p')
        {
            a[j++] = i;
        }
    }
    if(i == dim) return -1;
    return 0;
}

void mostrarArray(long d, long a[d])
{
    long i;
    for(i = 0 ; i < d ; i++)
    {
        if(i % 10 == 0) printf("\n");
        printf("%7ld", a[i]);
    }
    return;
}

void cribaErastotenes(long d, char c[d])
{
    long i, j;
    for(i = 1 ; i < d ; i++)
    {
        c[i] = 'p';
    }
    
    for(i = 2 ; i <= sqrt(d) ; i++)
    {
        if(c[i] == 'p')
        {
            for(j = 2 * i ; j < d ; j += i)
            {
                c[j] = 'c';
            }
        }
    }
    
    
}

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Compilation time: 0.13 sec, absolute running time: 0.13 sec, cpu time: 0.01 sec, memory peak: 3 Mb, absolute service time: 0.27 sec