rosettacode.org
For example, on this input:
-10 100
-10 101
-10 102
1000 5
1001 5
1002 5
-11 101
-9 101
1001 4
1001 6
-10 101
1001 5
> alive.$$
while read cells
do
echo $cells >> alive.$$
set x $cells
x=$2
y=$3
echo $x $((y-1))
echo $x $((y+1))
echo $((x-1)) $((y-1))
echo $((x-1)) $y
echo $((x-1)) $((y+1))
echo $((x+1)) $((y-1))
echo $((x+1)) $y
echo $((x+1)) $((y+1))
done | sort | uniq -c > neighbors.$$
grep '^ *3' < neighbors.$$ | sed -e 's/^ *[0-9].//'
grep '^ *2' < neighbors.$$ | sed -e 's/^ *[0-9].//' > has2.$$
sort alive.$$ -o alive.$$
comm -12 has2.$$ alive.$$
rm has2.$$ neighbors.$$ alive.$$ Must it use variables?
Must it have flow control?
Must it actually compute something?
Must it use non-primitive data structures?
Must it exhibit use of the language’s code organisation features?
...
One suggestion (from David Pearce) was Conway’s Game of Life: a simple simulation of finite automata. This seems like a good demonstration of most of the properties.
It is quite cool, though, to see a common problem solved in such a wide variety of languages.
s/all languages/lots of languages/g