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diff --git a/2022/nim/day07/src/main.nim b/2022/nim/day07/src/main.nim
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+++ b/2022/nim/day07/src/main.nim
@@ -0,0 +1,68 @@
+# Day 7: No Space Left On Device
+import std/[os, strutils]
+
+let input = paramStr(1).readFile().strip().split("\n")
+
+type File = object
+  id: string
+  size: int
+
+type Dir = ref object
+  id: string
+  files: seq[File]
+  dirs: seq[Dir]
+  parent: Dir
+  size: int
+
+var root = Dir(id: "/")
+var current = root
+for line in input[1..^1]:
+  let output = line.split(" ")
+  if output.len == 2:
+    if output[0] == "$":
+      discard
+    elif output[0] == "dir":
+      current.dirs.add(Dir(id: output[1], parent: current))
+    else:
+      current.files.add(File(id: output[1], size: output[0].parseInt()))
+  else:
+    assert output[1] == "cd"
+    if output[2] == "..":
+      current = current.parent
+    else:
+      for i in current.dirs:
+        if i.id == output[2]:
+          current = i
+          break
+
+proc update_size(a: Dir) =
+  for i in a.files:
+    a.size += i.size
+  for i in a.dirs:
+    i.update_size()
+    a.size += i.size
+root.update_size()
+
+const maximum_size = 100000
+
+var sum = 0
+proc calc_size(a: Dir) =
+  if a.size <= maximum_size:
+    sum += a.size
+  for i in a.dirs:
+    i.calc_size()
+root.calc_size()
+echo sum
+
+const total_space = 70000000
+const update_space = 30000000
+let needed_space = update_space - (total_space - root.size)
+
+var min = update_space
+proc calc_min(a: Dir) =
+  if a.size >= needed_space:
+    min = min(a.size, min)
+  for i in a.dirs:
+    i.calc_min()
+root.calc_min()
+echo min