%!PS

/gcd {
    {
        dup
        3 1 roll
        mod
        dup 0 eq {
            pop exit
        } if
    } loop
} bind def

48 18 gcd 6 eq { (Pass) } { (FAIL) } ifelse print ( ) print
18 48 gcd 6 eq { (Pass) } { (FAIL) } ifelse print ( ) print
24 54 gcd 6 eq { (Pass) } { (FAIL) } ifelse print ( ) print
54 24 gcd 6 eq { (Pass) } { (FAIL) } ifelse print ( ) print
12 8 gcd 4 eq { (Pass) } { (FAIL) } ifelse print ( ) print
8 12 gcd 4 eq { (Pass) } { (FAIL) } ifelse =

/ispower2 {
    dup 2 lt {
        pop false
    } {
        dup 1 sub and 0 eq
    } ifelse
} bind def

1 ispower2 false eq { (Pass) } { (FAIL) } ifelse print ( ) print
2 ispower2 true eq { (Pass) } { (FAIL) } ifelse print ( ) print
17 ispower2 false eq { (Pass) } { (FAIL) } ifelse print ( ) print
16 ispower2 true eq { (Pass) } { (FAIL) } ifelse =

/twofriendly {
    gcd ispower2
} bind def

8 24 twofriendly true eq { (Pass) } { (FAIL) } ifelse print ( ) print
26 39 twofriendly false eq { (Pass) } { (FAIL) } ifelse print ( ) print
4 10 twofriendly true eq { (Pass) } { (FAIL) } ifelse print ( ) print
1 2 twofriendly false eq { (Pass) } { (FAIL) } ifelse =