add day7

day7/day7.jl

@@ -0,0 +1,105 @@
+#!/usr/bin/env julia
+
+using Test
+
+mutable struct Dir
+  path :: String
+  dnames :: Vector{String}
+  fsize :: Int32
+end
+
+function get_dir_map(infile)
+  cwd = Vector{String}()
+  path = "/"
+  dirmap = Dict{String, Dir}()
+  open(infile, "r") do io
+    for line in eachline(io)
+      parts = split(line)
+      if parts[1] == "\$"
+        if parts[2] == "cd"
+          if parts[3] == "/"
+            empty!(cwd)
+          elseif parts[3] == ".."
+            pop!(cwd)
+          else
+            push!(cwd, parts[3])
+          end
+          path = "/" * join(cwd, '/')
+          if ! haskey(dirmap, path)
+            dirmap[path] = Dir(path, [], 0)
+          end
+        elseif parts[2] != "ls"
+          println("Unknown command: ", line)
+        end
+      else
+        parts = split(line, limit=2)
+        if parts[1] == "dir"
+          push!(dirmap[path].dnames, joinpath(path, parts[2]))
+        else
+          dirmap[path].fsize += parse(Int, parts[1])
+        end
+      end
+    end
+  end
+  for k in sort(collect(keys(dirmap)), by=p->length(p), rev=true)
+    v = dirmap[k]
+    for p in v.dnames
+      dirmap[k].fsize += dirmap[p].fsize
+    end
+  end
+  return dirmap
+end
+  
+
+function small_dir_sum(infile)
+  dirmap = get_dir_map(infile)
+  small_sum = 0
+  for v in values(dirmap)
+    if v.fsize <= 100000
+      small_sum += v.fsize
+    end
+  end
+  return small_sum
+end
+
+function delete_candidate_size(infile)
+  dirmap = get_dir_map(infile)
+  total = 70000000
+  want = 30000000
+  used = dirmap["/"].fsize
+  free = total - used
+  need = want - free
+  candidates = Vector{Int64}()
+  # println("used ", used)
+  # println("free ", free)
+  # println("need ", need)
+  for v in values(dirmap)
+    if v.fsize >= need
+      push!(candidates, v.fsize)
+    end
+  end
+  return minimum(candidates)
+end
+
+function test()
+  @testset "disk usage small dir sum" verbose=true begin
+    @test small_dir_sum("example.txt") == 95437
+    @test small_dir_sum("input.txt") == 1306611
+  end
+  @testset "disk usage delete candidate size" verbose=true begin
+    @test delete_candidate_size("example.txt") == 24933642
+    @test delete_candidate_size("input.txt") == 13210366
+  end
+end
+
+function main()
+  if size(ARGS, 1) == 0
+    test()
+  else
+    infile = ARGS[1]
+    println("infile = ", infile)
+    println("error priority sum: ", rucksack_errors(infile))
+  end
+end
+
+main()

day7/example.txt

@@ -0,0 +1,23 @@
+$ cd /
+$ ls
+dir a
+14848514 b.txt
+8504156 c.dat
+dir d
+$ cd a
+$ ls
+dir e
+29116 f
+2557 g
+62596 h.lst
+$ cd e
+$ ls
+584 i
+$ cd ..
+$ cd ..
+$ cd d
+$ ls
+4060174 j
+8033020 d.log
+5626152 d.ext
+7214296 k