Hello
I would like to learn lua and try to realize “kniht’s tour”. Although I know the proglematik and have made the program in several other languages more than once, in lua I do not succeed. Can someone tell me what is wrong here?
thank you in advance.
problemcode:
– kt-02-3.lua
– ******************************************************************
– works fine in: basic256, x11basic, algoid, euphoria, tcl, ring …
– version whitout grafik / With Warnsdorff’s rule (extended)
– ******************************************************************
–// possible moves
pm = {{-2,1},{-1,2},{1,2},{2,1},{-2,-1},{-1,-2},{1,-2},{2,-1}}
n = 8 --//number rows/collons
cbx = n --// rows
cby = n --// colls
–// startfeld ( 2/2 = kritisch!)
kx = 2 –
ky = 2 –
–// startfeld - randomizer (for testing)
math.randomseed (os.time ()) – random turn on
–kx =math.random(1, 8)
–ky =math.random(1, 8)
print(“Startfeld kx/ky: “…kx …”/”…ky)
–// make chessboard n*n
–cb = list(cby) for x in cb x = list(cbx) next ??
cb = {} – cb definition filled with nulls
for i = 1, n do
cb[i] = {}
for j = 1, n do
cb[i][j] = 0
end
end
function printCB() – cb printing
for y = 1, n do
io.write("|")
for x = 1, n do
if cb[y][x] <10 then
io.write(" “…cb[y][x]…”|" )
else
io.write( cb[y][x]…"|" )
end
end
print("")
end
return
end
–#-- between inclusive
–if nx >= 1 and nx <= N and ny >= 1 and ny <= N then – cb grenzen
function between(x, min, max)
return (x>=min) and (x<=max)
end
k = 0 --// jmps-counter
while(k < 65) do
cb[kx][ky] = k+1 – counter set
pq = {} – priority queue (clear)
for i = 1, n do
nx = kx + pm[i][1]; ny = ky + pm[i][2]
if between(nx, 1, cbx) and between(ny, 1, cby) then
if cb[nx][ny] == 0 then ctr = 1 – zaehler reset
for j = 1, n do
ex = nx + pm[j][1]; ey = ny + pm[j][2]
if between(ex, 1, cbx) and between(ey, 1, cby) then
if cb[ey][ex] == 0 then ctr=ctr+1 end
end
end --for j
table.insert(pq, (ctr*100)+i)
end – if cb[nx][ny]
end – if between…
end – for i
– Warnsdorff’s algorithmus; extended
– move to the neighbor that has min number of available neighbors
– randomization: we could take it - or not
if #pq > 0 then
table.sort (pq) – OK (min first)
minVal = 8 – max loop nr
minD = 0 – min value
math.randomseed (1,10) – random: 1-10
math.random(); math.random(); math.random(); --warming up
for dd = 1, #pq do
x = table.remove(pq,1) – kopf-element loeschen
p = math.floor(x / 100) – p wert extrahieren
m = x % 10 – m (row) wert extrahieren
if p == minVal and math.random() <5 then
minVal = p
minD = m
end
if p < minVal then
minVal = p
minD = m
end
end --dd
m = minD
kx = kx + pm[m][1]
ky = ky + pm[m][2]
else
if k < 63 then
print("Error in Field-No.: "…k)
break
else
print(" >>>-------------------> Success!")
break
end
end
k = k+1
end – while
– ****************** end main pgm ********************
printCB()
–[[
sometimes successful too:
| 33|30|37|20|23|16|49|18|
| 36| 1|34|31|38|19|22|15|
| 29|32|39|24|21|50|17|48|
| 2|35|28|59|46|61|14|57|
| 27|44|25|40|51|58|47|62|
| 6| 3|52|45|60|11|56|13|
| 43|26| 5| 8|41|54|63|10|
| 4| 7|42|53|64| 9|12|55|
]]
