Find limit of recursion
You are encouraged to solve this task according to the task description, using any language you may know.
Find the limit of recursion.
Batch File
MUNG.CMD is a commandline tool written in DOS Batch language. It finds the limit of recursion possible using CMD /C.
<lang dos>@echo off set /a c=c+1 echo [Depth %c%] Mung until no good cmd /c mung.cmd echo [Depth %c%] No good set /a c=c-1</lang>
Result (abbreviated):
... [Depth 259] Mung until no good [Depth 260] Mung until no good [Depth 261] Mung until no good [Depth 261] No good [Depth 260] No good [Depth 259] No good ...
If one uses call
rather than CMD/C
, the call depth is much deeper but ends abruptly and can't be trapped.
<lang dos> @echo off set /a c=c+1 echo [Depth %c%] Mung until no good call mung.cmd echo [Depth %c%] No good set /a c=c-1</lang>
Result (abbreviated):
1240: Mung until no good 1241: Mung until no good ****** B A T C H R E C U R S I O N exceeds STACK limits ****** Recursion Count=1240, Stack Usage=90 percent ****** B A T C H PROCESSING IS A B O R T E D ******
Tcl
<lang tcl>proc recur i {
puts "This is depth [incr i]" catch {recur $i}; # Trap error from going too deep
} recur 0</lang> The tail of the execution trace looks like this:
This is depth 995 This is depth 996 This is depth 997 This is depth 998 This is depth 999
VBScript
Haven't figured out how to see the depth. And this depth is that of calling the O/S rather than calling within.
<lang vb> 'mung.vbs option explicit
dim c if wscript.arguments.count = 1 then c = wscript.arguments(0) c = c + 1 else c = 0 end if wscript.echo "[Depth",c & "] Mung until no good." CreateObject("WScript.Shell").Run "cscript Mung.vbs " & c, 1, true wscript.echo "[Depth",c & "] no good." </lang>