# mozy contest: problem 1 PHP solution

Daniel C. dcrookston at gmail.com
Mon Nov 6 10:50:12 MST 2006

```You realize that this problem has been proved Turing-incomplete right?
There is no computer in the universe, and it is impossible to build
one, that can decide every string in that language.  I'm assuming they
only gave you strings that were small enough to be decideable, but
still, it's a bit funny that they picked this one.

Dan

On 11/6/06, Nicholas Leippe <nick at leippe.com> wrote:
> I don't have the text to the problem questions.  Maybe someone that saved them
> or someone from mozy will post them.  I'll just summarize them.
>
> The first problem was to evaluate a line full of parenthesis. If they were not
> balanced on the line output a 0.  If they were balanced, output the maximum
> nesting depth.
>
> <?
> while (\$line = fgets(STDIN)) {
>         \$mx = 0;
>         \$cur_depth = 0;
>         for (\$i = 0; \$i < strlen(\$line); \$i++) {
>                 \$p = \$line{\$i};
>                 if (\$p == '(') {
>                         \$cur_depth++;
>                 } else if (\$p == ')') {
>                         \$mx = max(\$mx, \$cur_depth);
>                         \$cur_depth--;
>                 }
>         }
>         if (\$cur_depth == 0) {
>                 echo "\$mx\n";
>         } else {
>                 echo "0\n";
>         }
> }
>
>
> /*
> PLUG: http://plug.org, #utah on irc.freenode.net
> Unsubscribe: http://plug.org/mailman/options/plug
> Don't fear the penguin.
> */
>

```