add day4 solution

day4.jl

@@ -0,0 +1,73 @@
+#!/usr/bin/env julia
+
+using DelimitedFiles
+
+infile = size(ARGS, 1) > 0 ? ARGS[1] : "day4input.txt"
+println("infile = ", infile)
+
+M = Matrix{Int64}[]
+B = Matrix{Bool}[]
+W = Int64[]
+S = Int64[]
+
+function mark_call(m::Matrix{Int64}, b::Matrix{Bool}, v::Int64)
+    score = 0
+    idx_list = findall(m .== v)
+    b[idx_list] .= true
+    for idx in idx_list
+        if (all(b[idx[1], :] .== true) || all(b[:, idx[2]] .== true))
+            score = sum(m[findall(b .== false)])
+        end
+        if score > 0
+            break
+        end
+    end
+    return score * v
+end
+
+open(infile, "r") do io
+    line1 = readuntil(io, "\n\n")
+    calls = vec(readdlm(IOBuffer(line1), ',', Int))
+    while true
+        line = readuntil(io, "\n\n")
+        if line == ""
+            break
+        else
+            push!(M, readdlm(IOBuffer(line), Int))
+            push!(B, fill(false, 5, 5))
+            push!(W, 0)
+            push!(S, 0)
+        end
+    end
+
+    score = 0
+    done = false
+    for (ncall, call) in enumerate(calls)
+        for i in 1:length(M)
+            m = M[i]
+            b = B[i]
+            score = mark_call(m, b, call)
+            if score > 0
+                println("Round ", ncall, " Winner ", i)
+                display(m)
+                println()
+                println(score)
+                if (W[i] == 0)
+                    W[i] = ncall
+                    S[i] = score
+                    if (all(W .!= 0))
+                        done = true
+                        break
+                    end
+                end
+            end
+        end
+        if (done)
+            break
+        end
+    end
+end
+
+max_ncall, max_i = findmax(W)
+println("last win ", max_i, " at ", max_ncall)
+println("score ", S[max_i])