awk code for stack and queue

[Frank Chen]

Anyone got awk code to implement stack/queue available?
Thanks!

-Frank
--
===============================================================================
| Chih-Hung Chen (Frank) | email: fr...@manua.gsfc.nasa.gov|
| General Sciences Corp.(SAIC) | fax : (301) 286-3221 |
| Software Development - SeaWiFS Data System| voice: (301) 286-9531 |
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[Michael S. Zraly]

fr...@manua.gsfc.nasa.gov (Frank Chen) writes:
>Anyone got awk code to implement stack/queue available?

# assuming nawk/gawk -- write code inline if you can't do functions

# stack: Use an array and an integer index thusly:

function st_push(val) {
st_array[st_pos++] = val;
}

function st_pop() {
return (st_size() > 0) ? "ERROR" : st_array[--st_pos];
}

function st_size() {
return st_pos;
}

# queue: Use an array and an two integer indices thusly:

function qu_add(val) {
qu_array[qu_tail++] = val;
}

function qu_del() {
return (qu_size() > 0) ? qu_array[qu_head++] : "ERROR";
}

function qu_size() {
return (qu_tail - qu_head);
}

--
Mike Zraly Nothing takes the taste out of peanut
mzr...@cs.umb.edu butter quite like unrequited love.
-- Charlie Brown

[jhe...@google.com]

There is a bug in the provided stack implementation. st_pop should have its conditional reversed:

return (st_size() > 0) ? st_array[--st_pos] : "ERROR";