hw1_philliry.in

." (1.)" cr \
." Hello World" cr cr

." (2.)" cr \ yeah, I don't know how to do that 
." ???"  cr cr

." (3.)" cr \ assuming integer arithmetic
\ 16 / 32 + 74 * 16 ^ 3 + 5 % 10
16 16 * 16 * 74 * 16 32 / + 5 10 mod + . cr cr

." (4.)" cr \ floating point or double?
\ 16.0 / 32.0 + 74.0 * 16.0 ^ 3.0 + 5 % 10
16e 16e f* 16e f* 74e f* 16e 32e f/ f+ 5e 10e fmod f+ f. cr cr

." (5.)" cr \
\ 16.0e0 / 32.0e0 + 74.0e0 * 16.0e0 ^ 3.0e0 + 5 % 10
16.0e0 16.0e0 f* 16.0e0 f* 74.0e0 f* 16.0e0 32.0e0 f/ f+ 5 10 mod s>f f+ f. cr cr

." (6.)" cr \
\ 16 / 32.0 + 74.0 * 16 ^ 3 + 5 % 10
16 16 * 16 * s>f 74e f* 16 s>f 32e f/ f+ 5 10 mod s>f f+ f. cr cr

." (7.)" cr \
\
\ y = 16;
\ x = 32.0e0;
\ y + x - 3.0e0 * 6 / 10.0 
\
VARIABLE y
16 y !
\ y . 247496  ok   ( it doesn't have to be this address!)
\ y @ .  16  ok
VARIABLE x
32.0e0 x f!
\ x f@ f. 32.
y @ s>f x f@ 3e 6 s>f f* 10e f/ f- f+ f. cr cr

." (8.)" cr \
\ if 5 < 3 then 7 else 2
: foo8 ( n1 < n2 ) < if 7 else 2 endif ;
5 3 foo8 . cr cr

." (9.)" cr \
\ if 5 > 3 then 7 else 2
: foo9 ( n1 < n2 ) > if 7 else 2 endif ;
5 3 foo9 . cr cr

." (10.)" cr \
\ for ( i = 0; i <= 5; i++ )
\	printf("%d ", i); 
\
: foo10 ( comment ) 6 0 ?DO i . LOOP ;
foo10 cr cr

." (11.) note: running '1 convertint' for demo" cr \
\ double convertint(int x)
\	{ return ((double)x); } 
\
: convertint ( int x -- double x ) s>f ;
1 convertint f. cr cr
\

." (12.) note: running '3...5 fact' for demo" cr \
\ int fact(int i)
\ {
\	if (i <= 0 ) return 1;
\	else return i*fact(i-1);
\ }
\
\ note: solution taken from gforth docs
\
: fact ( u -- u! ) 1 swap 1+ 1 u+do i * loop ;
\ we will need to produce some output, right?
3 fact . cr 
4 fact . cr 
5 fact . cr cr 

." (13.) note: running '0...3 fib' for demo" cr \
\ int fib(int i) {
\    if(i == 0) return 0;
\    else if(i == 1) return 1;
\    else return fib(i-1) + fib(i-2);
\ }
\
\ note: solution help from http://cubbi.com/fibonacci/forth.html
\ there are dozens of solutions on forth forums, but I don't fully understand any of the
\
: fib ( n -- sum up to n )
  dup 1 > if 
  1- dup 1- recurse swap recurse + then
;
0 fib . cr 
1 fib . cr 
2 fib . cr 
3 fib . cr cr

bye