Шрифт:
case EOF:
if (moreinput)
goto Again;
d.val = var->u.val = 0.0;
break;
case 0:
execerror("non-number read into", var->name);
break;
default:
d.val = 1.0;
break;
}
var->type = VAR;
push(d);
}
Inst *code(f) /* install one instruction or operand */
Inst f;
{
Inst *oprogp = progp;
if (progp >= &prog[NPROG])
execerror("program too big", (char*)0);
*progp++ = f;
return oprogp;
}
execute(p)
Inst *p;
{
for (pc = p; *pc != STOP && !returning; )
(*((++pc)[-1]));
}
3.7.4
double
proc double {
if ($1 > 1) {
double($1/2)
}
print($1)
}
double(1024)
3.7.5
fac
func fac {
if ($1 <= 0) return 1 else return $1 * fac($1-1)
}
3.7.6
fac1
func fac if ($1 <= 0) return 1 else return $1 * fac($1-1)
fac(0)
fac(7)
fac(10)
3.7.7
fac2
func fac {
if ($1 <= 0) {
return 1
}
return $1 * fac($1-1)
}
i=0
while(i<=20){
print "factorial of ", i, "is ", fac(i), "\n"
i=i+1
}
3.7.8
fib
proc fib {
a = 0
b = 1
while (b < $1) {
print b
c = b
b = a+b
a = c
}
print "\n"
}
3.7.9
fib2
{
n=0
a=0
b=1
while(b<10000000){
n=n+1
c=b
b=a+b
a=c
print(b)
}
print(n)
}
3.7.10
fibsum
proc fib{
a=1
b=1
c=2
d=3
sum = a+b+c+d
while(d<$1){
e=d+c
print(e)
a=b
b=c
c=d
d=e
sum=sum+e
}
print(sum)
}
fib(1000)
3.7.11
fibtest
proc fib {
a = 0
b = 1
while (b < $1) {
c = b
b = a+b
a = c
}
}
i = 1
while (i < 1000) {
fib(1000)
i = i + 1
}
3.7.12
hoc.h
typedef struct Symbol { /* symbol table entry */
char *name;
short type;
union {
double val; /* VAR */
double (*ptr); /* BLTIN */
int (*defn); /* FUNCTION, PROCEDURE */
char *str; /* STRING */
} u;
struct Symbol *next; /* to link to another */