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-rw-r--r--crawl-ref/source/util/lua/test/sort.lua66
1 files changed, 0 insertions, 66 deletions
diff --git a/crawl-ref/source/util/lua/test/sort.lua b/crawl-ref/source/util/lua/test/sort.lua
deleted file mode 100644
index 0bcb15f837..0000000000
--- a/crawl-ref/source/util/lua/test/sort.lua
+++ /dev/null
@@ -1,66 +0,0 @@
--- two implementations of a sort function
--- this is an example only. Lua has now a built-in function "sort"
-
--- extracted from Programming Pearls, page 110
-function qsort(x,l,u,f)
- if l<u then
- local m=math.random(u-(l-1))+l-1 -- choose a random pivot in range l..u
- x[l],x[m]=x[m],x[l] -- swap pivot to first position
- local t=x[l] -- pivot value
- m=l
- local i=l+1
- while i<=u do
- -- invariant: x[l+1..m] < t <= x[m+1..i-1]
- if f(x[i],t) then
- m=m+1
- x[m],x[i]=x[i],x[m] -- swap x[i] and x[m]
- end
- i=i+1
- end
- x[l],x[m]=x[m],x[l] -- swap pivot to a valid place
- -- x[l+1..m-1] < x[m] <= x[m+1..u]
- qsort(x,l,m-1,f)
- qsort(x,m+1,u,f)
- end
-end
-
-function selectionsort(x,n,f)
- local i=1
- while i<=n do
- local m,j=i,i+1
- while j<=n do
- if f(x[j],x[m]) then m=j end
- j=j+1
- end
- x[i],x[m]=x[m],x[i] -- swap x[i] and x[m]
- i=i+1
- end
-end
-
-function show(m,x)
- io.write(m,"\n\t")
- local i=1
- while x[i] do
- io.write(x[i])
- i=i+1
- if x[i] then io.write(",") end
- end
- io.write("\n")
-end
-
-function testsorts(x)
- local n=1
- while x[n] do n=n+1 end; n=n-1 -- count elements
- show("original",x)
- qsort(x,1,n,function (x,y) return x<y end)
- show("after quicksort",x)
- selectionsort(x,n,function (x,y) return x>y end)
- show("after reverse selection sort",x)
- qsort(x,1,n,function (x,y) return x<y end)
- show("after quicksort again",x)
-end
-
--- array to be sorted
-x={"Jan","Feb","Mar","Apr","May","Jun","Jul","Aug","Sep","Oct","Nov","Dec"}
-
-testsorts(x)