#include <stdio.h>
#include <stdlib.h>

#define max2( x, y )  (x) > (y) ? (x) : (y)
#define max4(a, b, c, d)    max2 ( max2 ( (a), (b) ), max2 ( (c), (d) ) )

int
main ( void )
{
    printf ( "Max: %d\n", max4 ( 10, 20, 30, 40 ) );
    printf ( "Max: %d\n", max4 ( 10, 0, 3, 4 ) );
    return EXIT_SUCCESS;
}