day 12

day12/input

@@ -0,0 +1,41 @@
+abccccaaacaccccaaaaacccccccaaccccccccaaaaaaccccccaaaaaccccccccccaaaaaaaaacccccccaaaaaaaaaaaaaaccaaaaaccccccccccccaccacccccccccccccccccccccccccccccccccccccccaaaaaa
+abccaacaaaaaccaaaaacccccaaaaaccccccccaaaaaaccccccaaaaaacccccccccaaaaaaaaaaaaacccaaaaaaaaaaaaaaaaaaaaaccccccccccccaaaacccccccccccccccccccccccccccccccccccccccaaaaaa
+abccaaaaaaaaccaaaaaacccccaaaaaccccccaaaaaaaacccccaaaaaaccccccccccaaaaaaaaaaaacccaaaaaacaaaaaacaaaaaaaaccccccccccaaaaacccccaccccccccccccccccccaaacccccccccccccaaaaa
+abcccaaaaaccccccaaaacccccaaaaacccccaaaaaaaaaaccccaaaaaacccccccccaaaaaaaaaaaaaacaaaaaaaaaaaaaacaaaaaaaaccccccccccaaaaaacccaaacccccccccccccccccaaaccccccccccccccaaaa
+abaaacaaaaacccccacccccccaaaaaccccccaaaaaaaaaaccccccaaaccccccccccaaaaaaaaacaaaaaaaaaaaaaaaaaaacccaaacaccaaaccccccaaaaaaaacaaacccccccccccaaccccaaacccccccccccccccaac
+abaaacaacaaaaccccccccccccccaaccccccacaaaaacccccaacccccccccccccccaaaacaaaaaaaaaacccaacccaaacaacccaaccccaaaaccccccccaacaaaaaaaaaaccccccccaaaaccaaaccccccccccccccaaac
+abaaccaaccaaacacccccccccccccccccccccccaaaacccaaaaaaccaaaccccccccccaacaaaaaaaaaacccaaccccccccccccccccccaaaaccccccccccccaaaaaaaaaccccccciiiiiaaaaacccccccccccccccccc
+abaaccccaaaaaaaacccccccccccccccccccccccaaccccaaaaaaccaaaaaccccacccaaccaaacaaaaacccccccccccccccaacccccccaaaccccccccccccccaaaaacccccccciiiiiiiiaaaaaccccccaaaccccccc
+abaaacccaaaaaaaacccccccccccccccccccccccccccccaaaaaacaaaaaccccaaaaaaaccaaccaaacccccccaaaaacacccaaccccccccccaacccccccccccaaaaaaccccccciiiiiiiiijjaaaaaccccaaacaccccc
+abaaaccccaaaaaaccccccccccccccccccccaaccccccccaaaaaccaaaaacccccaaaaaaaaccccccccccccccaaaaaaaaaaaaccccccccccaaacaaccccccaaaaaaaccccccciiinnnnoijjjjjjjjjjaaaaaaacccc
+abccccccccaaaaacccccaacccccccccccaaaacccccccccaaaacccaaaaaccccaaaaaaaaacccccccccccccaaaaaaaaaaaaaaccccccccaaaaaacccaacaaacaaacccccchhinnnnnoojjjjjjjjjkkaaaaaacccc
+abcccccccaaaaaacaaacaacccccccccccaaaaaaccccccccccccccaacccccccaaaaaaaaacaaccccccccccaaaaaaaaaaaaaaacccccaaaaaaacccaaaaccccccacaaccchhinnnnnoooojjjjjjkkkkaaaaccccc
+abaacccaccaaaccccaaaaaccccccccccccaaaaccccccccccccccccccccccccaaaaaaaacaaaaaaaccccccaaaaaaaaaaaaaaacccccaaaaaaacccaaaaccccaaacaaachhhnnntttuooooooooppkkkaaaaccccc
+abaacccaaaaaaaccccaaaaaacccccccccaaaaaccccccccccccccccccccccccaaaaaaacccaaaaacccccccccaaacaaaaaaaaccccccccaaaaacccaaaacccccaaaaacchhhnnnttttuooooooppppkkkaaaccccc
+abaacccaaaaaaccccaaaaaaacccccccccaacaaccccccccccccccccccccccaaaccaaaccaaaaaaacccccccccccccaaaaaaaccccccaacaacaaacccccccccccaaaaaahhhhnntttttuuouuuuupppkkkcccccccc
+abaaaacaaaaaaaaaaaaaaacccccccccccccccccccccccccccccccccccccaaaacccaaacaaaaaaaaccccccccccccaccaaaccccccaaacaaccccccccccccccaaaaaahhhhnnntttxxxuuuuuuupppkkkcccccccc
+abaaaacaaaaaaaaaaacaaacccaaacccccccccccccccccccccacccccccccaaaacccccccaaaaaaaaccccccccccccccccaaacccccaaacaaacccccccccccccaaaaaahhhhmnnttxxxxuuyuuuuuppkkkcccccccc
+abaaaccaaaaaaaaccccaaaccccaaaccacccccccccccaaaaaaaaccccccccaaaacccccccccaaacaacccccccccccccccccccccaaaaaaaaaacccccacccccccaacaghhhmmmmtttxxxxxxyyyuupppkkccccccccc
+abaaccaaaaaaaccccccccccccaaaaaaaacccccccccccaaaaaaccccccccccccccccccccccaaccccccaacccccccccccccccccaaaaaaaaacccccaaccccccccccagggmmmmttttxxxxxyyyyvvppkkkccccccccc
+abaacccaccaaacccccccccccaaaaaaaaccccccccccccaaaaaaccccccccccccccccccccccccccaaacaaaccccccccccccccccccaaaaaccccaaaaacaacccccccgggmmmmttttxxxxxyyyyvvpppiiiccccccccc
+SbaaaaaccccaaccccccccccaaaaaaaaacacccccccccaaaaaaaacccccccccccccccaacccccccccaaaaaccccccccccaaaacccccaaaaaacccaaaaaaaaccaaaccgggmmmsssxxxEzzzzyyvvvpppiiiccccccccc
+abaaaaaccccccccccccccccaaaaaaaaaaaaaaaaaccaaaaaaaaaacccccccccccaaaaacccccccccaaaaaaaccccccccaaaaaccccaaaaaaaccccaaaaacccaaaaagggmmmsssxxxxxyyyyyyvvqqqiiiccccccccc
+abaaaaacccccccccccccccccaaaaaaaacaaaaaacccaaaaaaaaaaccccccccccccaaaaacccccccaaaaaaaacccccccaaaaaaccccaaacaaacccaaaaacccaaaaaagggmmmssswwwwwyyyyyyyvvqqqiiicccccccc
+abaaaaccccccccccccccccccccaaaaaaaaaaaaacccacacaaacccccccccccccccaaaaacccccccaaaaaaaacccccccaaaaaaccccacccccccccaacaaaccaaaaaagggmmmsssswwwwyyyyyyyvvvqqiiicccccccc
+abaaaaacccccccccccccccccccaacccaaaaaaaaaccccccaaaccccccccccccccaaaaaccccccccaacaaacccccccccaaaaaacccccccccccccccccaaccccaaaaagggmmmmssssswwyywwvvvvvvqqiiicccccccc
+abaaaaaccccccccccccccccccaaacccaaaaaaaaaacccccaaaccccccaacccccccccaaccaaccccccaaaacaccccaacccaacccccccccccccccccccccccccaaaaccggglllllssswwwywwwvvvvqqqiiicccccccc
+abaccccccccccccccccccccccccccccaaaaaaaaaaccccaaaacccaaaacccccccccccccaaaccccccaaaaaaaaaaaacccccccccccccccccccccccccccccccccccccffffllllsswwwwwwrrqvqqqqiiicccccccc
+abccccccccccccccccccccccccccccccccaaacacaccccaaaacccaaaaaacccccccccaaaaaaaaccccaaaaaaaaaaaacccccccccccccccccccccccccccccccccccccfffflllssrwwwwrrrqqqqqqjjicccccccc
+abcccccccaaaccccccccaaccccccccccccaaacccccccccaaaccccaaaaacccccccccaaaaaaaaccaaaaaaacaaaaaaacccccccccccccccccccccccccccccccccccccfffflllrrwwwrrrrqqqqjjjjjcccccccc
+abaaaccaaaaacccccccaaacaaccccccccccaacccccccccccccccaaaaacccccccccccaaaaaacccaaaaaaaaaaaaaaaccccccccccccccccccccccccccccccccccccccffffllrrrrrrrkjjjjjjjjjcccaccccc
+abaaaccaaaaaacccccccaaaaacaacaaccccccccccccccccccccccccaacccccccccccaaaaaacccaaaaaaaaaaaaacccccccccccccccccccccccccccccccccccccccccfffllrrrrrrkkjjjjjjjcccccaccccc
+abaaaccaaaaaacccccaaaaaaccaaaaacccccccccccccccccccccccccccccccccccccaaaaaacccccaaacaaaaaaacccccccccccccccccccccccccccccccccccccccccfffllkkrrrkkkjjddcccccccaaacccc
+abaaaccaaaaaccccccaaaaaaaacaaaaaccccccccccccccccccccccccccccccccccccaaacaacccccaaaccccccaaaaccccaaaccccccccccccccccaaaccccccccccccccfeekkkkkkkkkdddddccccaaaaacccc
+abaaacccaaaaccccccaacaaaaaaaaaaaccccccccccccccccccccccccccccccccccccccaacaacccccccccccccccaaccccaaaacccccccccccccccaaaacccccccccccccceeekkkkkkdddddddcccaaacaccccc
+abaccccccccccccccccccaacccaaaaccccccccccccccccccccccccccccaaccaaccaacccaaaaccccccccccccaaaaaaaacaaaacccccccccccccccaaaacccaaaaacccccceeeekkkkdddddaaccccaacccccccc
+abccccccccccccccccccaaccccccaaccccccccccccaaacccccccccccccaaaaaaccaaaacaaaaacccccccccccaaaaaaaacaaaccccccccccccccccaaaacccaaaaaccccccceeeeeeedddcacacccccccccccccc
+abccccccccccccccccccccccccccccccccccccccccaaaacaacccccccccaaaaacccaaaaaaaaaaccccccccccccaaaaaacccccccccccccccccccccccccccaaaaaacccccccaeeeeeeddcccccccccccccccaaac
+abccccccccccccccccccccccccccccccccccccccccaaaaaaacccccccccaaaaaaccaaaaaaaacaccccccaaacaaaaaaaacccccccccccccccccccccccccccaaaaaacccccccccceeeeaaccccccccccccccccaaa
+abcccccccccccccccccccccccccccccccccccccccccaaaaaaccccccccaaaaaaaaccaaaaaaaccccccccaaaaaaaaaaaacccccccccccccccccccccccccccaaaaaacccccccccccccaaaccccccccccccccccaaa
+abccccccccccccccccccccccccccccccccccccccaaaaaaaaccccaaaccaaaaaaaacaaaaaaaaaacccccccaaaaaaaccaacccccccccccccccccccccccccccccaacccccccccccccccaaaccccccccccccccaaaaa
+abccccccccccccccccccccccccccccccccccccccaaaaaaaaacccaaaaccccaaccaaaaaaaaaaaaaccccaaaaaaaaaacccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccccaaaaaa

day12/task1.nim

@@ -0,0 +1,84 @@
+import system/io
+import strutils
+import sequtils
+import tables
+import sugar
+
+const
+  SYM_START = 'S'
+  SYM_END = 'E'
+
+type
+  Coords = tuple
+    x, y: int
+
+proc diff(a, b: int): int =
+  if a > b: a - b
+  else: b - a
+
+proc height(i: char): int =
+  (
+    case i:
+      of SYM_START:
+        'a'
+      of SYM_END:
+        'z'
+      else:
+        i
+  ).ord
+
+var startPoint: Coords
+var endPoint: Coords
+var adjacents = initTable[Coords, seq[Coords]]()
+
+let heightMap = collect(
+  for line in stdin.readAll.split:
+    if line != "": line
+)
+
+for x in 0 .. heightMap.len - 1:
+  for y in 0 .. heightMap[x].len - 1:
+    var adjs = newSeq[Coords](0)
+
+    let h = heightMap[x][y].height
+
+    case heightMap[x][y]:
+      of SYM_START:
+        startPoint = (x, y)
+      of SYM_END:
+        endPoint = (x, y)
+      else: discard
+
+    if y > 0 and h - heightMap[x][y - 1].height < 2:
+      adjs.add((x, y - 1))
+    if y < heightMap[x].len - 1 and h - heightMap[x][y + 1].height < 2:
+      adjs.add((x, y + 1))
+    if x > 0 and h - heightMap[x - 1][y].height < 2:
+      adjs.add((x - 1, y))
+    if x < heightMap.len - 1 and h - heightMap[x + 1][y].height < 2:
+      adjs.add((x + 1, y))
+
+    adjacents[(x, y)] = adjs
+
+var unvisited = adjacents.keys.toSeq
+var shortest = collect(initTable()):
+  for node in unvisited:
+    {node: high(int) - 1}
+
+shortest[endPoint] = 0
+
+while unvisited.len != 0:
+  var current_min: Coords = (-1, -1)
+
+  for node in unvisited:
+    if current_min.x == -1 or shortest[node] < shortest[current_min]:
+      current_min = node
+
+  for adj in adjacents[current_min]:
+    let t = shortest[current_min] + 1
+    if t < shortest[adj]:
+      shortest[adj] = t
+
+  unvisited.del(unvisited.find(current_min))
+
+echo shortest[startPoint]

day12/task2.nim

@@ -0,0 +1,93 @@
+import system/io
+import strutils
+import sequtils
+import tables
+import sugar
+
+const
+  SYM_START = 'S'
+  SYM_END = 'E'
+  SYM_LOWEST = 'a'
+
+type
+  Coords = tuple
+    x, y: int
+
+proc diff(a, b: int): int =
+  if a > b: a - b
+  else: b - a
+
+proc height(i: char): int =
+  (
+    case i:
+      of SYM_START:
+        'a'
+      of SYM_END:
+        'z'
+      else:
+        i
+  ).ord
+
+var startPoint: Coords
+var endPoint: Coords
+var lowestPoints = newSeq[Coords]()
+var adjacents = initTable[Coords, seq[Coords]]()
+
+let heightMap = collect(
+  for line in stdin.readAll.split:
+    if line != "": line
+)
+
+for x in 0 .. heightMap.len - 1:
+  for y in 0 .. heightMap[x].len - 1:
+    var adjs = newSeq[Coords](0)
+
+    let h = heightMap[x][y].height
+
+    case heightMap[x][y]:
+      of SYM_START:
+        startPoint = (x, y)
+      of SYM_END:
+        endPoint = (x, y)
+      of SYM_LOWEST:
+        lowestPoints.add((x, y))
+      else: discard
+
+    if y > 0 and h - heightMap[x][y - 1].height < 2:
+      adjs.add((x, y - 1))
+    if y < heightMap[x].len - 1 and h - heightMap[x][y + 1].height < 2:
+      adjs.add((x, y + 1))
+    if x > 0 and h - heightMap[x - 1][y].height < 2:
+      adjs.add((x - 1, y))
+    if x < heightMap.len - 1 and h - heightMap[x + 1][y].height < 2:
+      adjs.add((x + 1, y))
+
+    adjacents[(x, y)] = adjs
+
+var unvisited = adjacents.keys.toSeq
+var shortest = collect(initTable()):
+  for node in unvisited:
+    {node: high(int) - 1}
+
+shortest[endPoint] = 0
+
+while unvisited.len != 0:
+  var current_min: Coords = (-1, -1)
+
+  for node in unvisited:
+    if current_min.x == -1 or shortest[node] < shortest[current_min]:
+      current_min = node
+
+  for adj in adjacents[current_min]:
+    let t = shortest[current_min] + 1
+    if t < shortest[adj]:
+      shortest[adj] = t
+
+  unvisited.del(unvisited.find(current_min))
+
+var min = high(int)
+for node in lowestPoints:
+  if shortest[node] < min:
+    min = shortest[node]
+
+echo min

day12/test_input

@@ -0,0 +1,5 @@
+Sabqponm
+abcryxxl
+accszExk
+acctuvwj
+abdefghi