Editing Dc (computer program) (section)

===Summing the entire stack===

This is implemented with a macro stored in register <code>a</code> which conditionally calls itself, performing an addition each time, until only one value remains on the stack. The <code>z</code> operator is used to push the number of entries in the stack onto the stack. The comparison operator <code>&gt;</code> pops two values off the stack in making the comparison. 

<syntaxhighlight lang="bash">
dc -e "1 2 4 8 16 100 0d[+z1<a]dsaxp"
</syntaxhighlight>

And the result is 131.