Add day 7 solutions

day7.chpl

@@ -0,0 +1,74 @@
+use IO, Map, List;
+
+class TreeNode {
+  var name: string;
+  var parent: borrowed TreeNode?;
+
+  var files = new map(string, int);
+  var dirs = new list(owned TreeNode);
+
+  var size = -1;
+
+  proc init(name: string, parent: borrowed TreeNode?) {
+    this.name = name;
+    this.parent = parent;
+  }
+
+  /*
+
+  ```Chapel
+  iter these(param tag: iterKind): (string, int) where tag == iterKind.standalone {
+    var size = + reduce files.values();
+    coforall dir in dirs with (+ reduce size) {
+      // Yield directory sizes from the dir.
+      forall subSize in dir do yield subSize;
+      // Count its size for our size.
+      size += dir.size;
+    }
+    yield (name, size);
+    this.size = size;
+  }
+  ```
+
+  */
+
+  iter these(): (string, int) {
+    var size = + reduce files.values();
+    for dir in dirs {
+      // Yield directory sizes from the dir.
+      for subSize in dir.these() do yield subSize;
+      // Count its size for our size.
+      size += dir.size;
+    }
+    yield (name, size);
+    this.size = size;
+  }
+}
+
+var rootFolder: owned TreeNode = new owned TreeNode("", nil);
+var currentFolder: borrowed TreeNode = rootFolder.borrow();
+
+for line in stdin.lines() {
+  const strippedLine = line.strip();
+  if strippedLine == "$ cd .." {
+    if const parent = currentFolder.parent then
+      currentFolder = parent;
+  } else if strippedLine.startsWith("$ cd ") {
+    const dirName = strippedLine["$ cd ".size..];
+    var newFolder = new owned TreeNode(dirName, currentFolder);
+    currentFolder.dirs.append(newFolder);
+    currentFolder = currentFolder.dirs.last().borrow();
+  } else if !strippedLine.startsWith("$ ls") {
+    const (sizeOrDir, _, name) = strippedLine.partition(" ");
+    if sizeOrDir == "dir" {
+      // Ignore directories, we'll CD into them.
+    } else {
+      currentFolder.files[name] = sizeOrDir : int;
+    }
+  }
+}
+
+writeln(+ reduce [(_, size) in rootFolder] if size < 100000 then size);
+
+const toDelete = rootFolder.size - 40000000;
+writeln(min reduce [(_, size) in rootFolder] if size >= toDelete then size);

day7.cr

@@ -0,0 +1,64 @@
+require "advent"
+INPUT = input(2022, 7).lines[1..]
+
+class DirTree
+  property name : String
+  property files : Hash(String, Int64)
+  property subDirs : Array(DirTree)
+  property parent : DirTree?
+
+  def initialize(@name, @parent)
+    @files = {} of String => Int64
+    @subDirs= [] of DirTree
+    @parent.try &.subDirs.<<(self)
+  end
+
+  def sum_yielding(&block : Int32 ->): Int32
+    size = 0
+    size += @subDirs.sum do |x|
+      x.sum_yielding(&block)
+    end
+    size += @files.sum { |k,v| v }
+    yield size
+    return size
+  end
+end
+
+dir = DirTree.new("", nil)
+
+INPUT.each do |line|
+  if line =~ /\$ cd (.+)$/
+    if $1 == ".."
+      dir = dir.parent.not_nil!
+    else
+      dir = DirTree.new($1, dir)
+    end
+  elsif line == "$ ls"
+  else
+    x, y = line.split(" ")
+    if x == "dir"
+    else
+      dir.files[y] = x.to_i64
+    end
+  end
+end
+
+while par = dir.parent
+  dir = par
+end
+
+total = 0
+outer_size = dir.sum_yielding do |i|
+  total += i if i <= 100000
+end
+puts total
+
+puts "Used: #{outer_size}"
+puts "Unused: #{70000000 -  outer_size}"
+to_delete = 30000000 - (70000000 - outer_size)
+puts "To delete: #{to_delete}"
+big_enough = [] of Int32
+outer_size = dir.sum_yielding do |i|
+  big_enough << i if i >= to_delete
+end
+puts big_enough.min