blob: d887aae60c62e92ba8ca2b24f8d164900aae1c94 (
plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
|
#!/usr/bin/perl
use lib '..';
use Memoize;
if (-e '.fast') {
print "1..0\n";
exit 0;
}
print "# Warning: I'm testing the speedup. This might take up to sixty seconds.\n";
print "1..6\n";
sub fib {
my $n = shift;
$COUNT++;
return $n if $n < 2;
fib($n-1) + fib($n-2);
}
$N = 0;
$ELAPSED = 0;
until ($ELAPSED > 10) {
$N++;
my $start = time;
$COUNT=0;
$RESULT = fib($N);
$ELAPSED = time - $start;
print "# fib($N) took $ELAPSED seconds.\n" if $N % 1 == 0;
}
print "# OK, fib($N) was slow enough; it took $ELAPSED seconds.\n";
&memoize('fib');
$COUNT=0;
$start = time;
$RESULT2 = fib($N);
$ELAPSED2 = time - $start + .001; # prevent division by 0 errors
print (($RESULT == $RESULT2) ? "ok 1\n" : "not ok 1\n");
# If it's not ten times as fast, something is seriously wrong.
print (($ELAPSED/$ELAPSED2 > 10) ? "ok 2\n" : "not ok 2\n");
# If it called the function more than $N times, it wasn't memoized properly
print (($COUNT > $N) ? "ok 3\n" : "not ok 3\n");
# Do it again. Should be even faster this time.
$start = time;
$RESULT2 = fib($N);
$ELAPSED2 = time - $start + .001; # prevent division by 0 errors
print (($RESULT == $RESULT2) ? "ok 4\n" : "not ok 4\n");
print (($ELAPSED/$ELAPSED2 > 10) ? "ok 5\n" : "not ok 5\n");
# This time it shouldn't have called the function at all.
print ($COUNT ? "ok 6\n" : "not ok 6\n");
|
