COLOR.C

#include "stdio.h"

void setInk( int ink )
{
    static int previous = -9999;

    if ( previous != ink )
    {
        previous = ink;
        printf( "\033[38;5;%dm", ink );
    }
}

void setPaper( int paper )
{
    static int previous = -9999;

    if ( previous != paper )
    {
        previous = paper;
        printf( "\033[48;5;%dm", paper );
    }
}

void restoreDefaults( void )
{
    printf( "\033[0m" );
}

void main( void )
{
    int x, y, count, maxitr;
    float creal, cimag;
    float zreal, zimag;
    float zm, zn, zl, zr2;

    maxitr = 24;
    for ( y = -39; y <= 39; ++y )
    {
        for ( x = -39; x <= 39; ++x )
        {
            creal = x / 20.;
            cimag = y / 20.;
            zreal = creal;
            zimag = cimag;
            for ( count = 1; count < maxitr; ++count )
            {
                zm  =  zreal * zreal;
                zn  =  zimag * zimag;
                zl  =  zm + zn;
                if ( zl > 4. )
                {
                    break;
                }
                zr2 = zm - zn + creal;
                zimag = zreal * zimag * 2. + cimag;
                zreal = zr2;
            }
            setInk( 184 - ( 7 * count ) );
            setPaper( 232 + count );
            /* put down a tick */
            printf( "#" );
        }
        printf( "\n" );
        if ( getk() )
        {
            break;
        }
    }
    restoreDefaults();
}