1 files changed, 92 insertions, 0 deletions
diff --git a/day16.rb b/day16.rb
new file mode 100644
index 0000000..782e9bd
--- /dev/null
+++ b/day16.rb
@@ -0,0 +1,92 @@
+def op(cmd, regs)
+  regs2 = regs.dup
+
+  case cmd[0]
+  when :addr; regs2[cmd[3]] = regs[cmd[1]] + regs[cmd[2]]
+  when :addi; regs2[cmd[3]] = regs[cmd[1]] + cmd[2]
+  when :mulr; regs2[cmd[3]] = regs[cmd[1]] * regs[cmd[2]]
+  when :muli; regs2[cmd[3]] = regs[cmd[1]] * cmd[2]
+  when :banr; regs2[cmd[3]] = regs[cmd[1]] & regs[cmd[2]]
+  when :bani; regs2[cmd[3]] = regs[cmd[1]] & cmd[2]
+  when :borr; regs2[cmd[3]] = regs[cmd[1]] | regs[cmd[2]]
+  when :bori; regs2[cmd[3]] = regs[cmd[1]] | cmd[2]
+  when :setr; regs2[cmd[3]] = regs[cmd[1]]
+  when :seti; regs2[cmd[3]] = cmd[1]
+  when :gtir; regs2[cmd[3]] = cmd[1] > regs[cmd[2]] ? 1 : 0
+  when :gtri; regs2[cmd[3]] = regs[cmd[1]] > cmd[2] ? 1 : 0
+  when :gtrr; regs2[cmd[3]] = regs[cmd[1]] > regs[cmd[2]] ? 1 : 0
+  when :eqri; regs2[cmd[3]] = regs[cmd[1]] == cmd[2] ? 1 : 0
+  when :eqir; regs2[cmd[3]] = cmd[1] == regs[cmd[2]] ? 1 : 0
+  when :eqrr; regs2[cmd[3]] = regs[cmd[1]] == regs[cmd[2]] ? 1 : 0
+  end
+
+  regs2
+end
+
+OPS = [:addr, :addi, :mulr, :muli, :banr, :bani, :borr, :bori, :setr, :seti,
+ :gtri, :gtir, :gtrr, :eqri, :eqir, :eqrr]
+
+OPS.each { |o|
+  
+  if op([o, 2, 1, 2], [3, 2, 1, 1]) == [3, 2, 2, 1]
+    p o
+  end
+}
+
+p1 = 0
+
+poss = Array.new(16) { OPS }
+
+code = nil
+
+File.read("day16").split("\n\n").each { |samp|
+  if samp =~ /^Before:/
+    x = samp.lines.map { |l| l.scan(/\[.*?\]/) }
+    before = eval(x[0].first)
+    unop, *args = samp.lines[1].split(' ').map(&:to_i)
+    after = eval(x[2].first)
+
+    n = OPS.find_all { |o|
+      op([o, *args], before) == after
+    }
+    
+    poss[unop] &= n
+
+    if n.size >= 3
+      p1 += 1
+    end
+  else
+    code = samp
+  end
+}
+
+p p1
+
+require 'pp'
+
+pp poss
+
+loop {
+  det = poss.find_all { |p| p.size == 1 }.flatten
+  break  if det.size == 16
+  poss.each_index { |i|
+    poss[i] -= det  unless poss[i].size == 1
+  }
+}
+
+poss.map!(&:first)
+
+p poss
+
+regs = [0,0,0,0]
+code.each_line { |l|
+  numop, *args = l.split(' ').map(&:to_i)
+  regs = op([poss[numop], *args], regs)
+}
+p regs[0]
+
+__END__
+
+Before: [3, 2, 1, 1]
+9 2 1 2
+After:  [3, 2, 2, 1]