I've recently started learning Ruby, I cannot seem to locate the
cause of this error. Please pardon me if the answer is more
straightforward as it seems.
I've double-checked, blkcheck method works fine. I suspect the
problem lies with line 32, Blk.each ..., however, I don't see why
a problem should be there. Please help shed some light.
The error message:
../creat.rb:25:in `blkcheck': undefined method `[]' for nil:NilClass
(NoMethodError)
from ./creat.rb:25:in `times'
from ./creat.rb:25:in `blkcheck'
from ./creat.rb:24:in `times'
from ./creat.rb:24:in `blkcheck'
from ./creat.rb:33:in `blkscheck'
from ./creat.rb:32:in `each'
from ./creat.rb:32:in `blkscheck'
from ./creat.rb:45
The src:
1 #!/usr/bin/ruby
2
3 Val = [1, 2, 3, 4, 5, 6, 7, 8, 9]
4 Blk = [[0,0],[0,3],[0,6],[3,0],[3,3],[3,6],[6,0],[6,3],[6,6]]
5
6 def linescheck (tab)
7 num = 0
8 9.times { |i| num += 1 if tab[i].sort == Val }
9 1 if num == 9
10 end
11
12 def colscheck (tab)
13 num = 0
14 9.times do |i|
15 tmp = []
16 9.times { |j| tmp <<= tab[j][i] }
17 num += 1 if tmp.sort == Val
18 end
19 1 if num == 9
20 end
21
22 def blkcheck (tab, i, j)
23 tmp = []
24 3.times do |k|
25 3.times { |l| tmp <<= tab[i+k+l][j+k] }
26 end
27 1 if tmp.sort == Val
28 end
29
30 def blkscheck (tab)
31 num = 0
32 Blk.each do |i,j|
33 num += 1 if blkcheck(tab,i,j)
34 end
35 1 if num == 9
36 end
37
38 # Create the table of values
39 val = []
40 9.times do |i|
41 val <<= Val
42 end
43
44 #blkscheck(val)
45 print "Hello world!\n" unless blkscheck(val)
