Fix some rubocop warnings

advent-of-code/2024/day_06/lib.rb

@@ -2,91 +2,90 @@ def walk(matrix)
   should_continue = true
 
   i, j = get_current_position(matrix)
-  start_i, start_j = i, j
+  start_i = i
+  start_j = j
   start_symbol = matrix[i][j]
 
-  history = Hash.new
+  history = {}
 
-  while should_continue do
+  while should_continue
     history["#{i},#{j}"] = true
     should_continue, i, j = make_step(matrix, i, j)
   end
 
   matrix[start_i][start_j] = start_symbol
-  return history.length
+  history.length
 end
 
 def make_step(matrix, i, j)
   case matrix[i][j]
-    when "^"
+  when '^'
     if i == 0
-        matrix[i][j] = "."
+      matrix[i][j] = '.'
       return [false, -1, -1]
     end
 
-      if matrix[i-1][j] == "#"
+    if matrix[i - 1][j] == '#'
-        matrix[i][j] = ">"
+      matrix[i][j] = '>'
       return [true, i, j]
     end
 
-      matrix[i-1][j] = "^"
+    matrix[i - 1][j] = '^'
-      matrix[i][j] = "."
+    matrix[i][j] = '.'
-      return [true, i-1, j]
+    [true, i - 1, j]
-    when "v"
+  when 'v'
-      if i == matrix.length-1
+    if i == matrix.length - 1
-        matrix[i][j] = "."
+      matrix[i][j] = '.'
       return [false, -1, -1]
     end
 
-      if matrix[i+1][j] == "#"
+    if matrix[i + 1][j] == '#'
-        matrix[i][j] = "<"
+      matrix[i][j] = '<'
       return [true, i, j]
     end
 
-      matrix[i+1][j] = "v"
+    matrix[i + 1][j] = 'v'
-      matrix[i][j] = "."
+    matrix[i][j] = '.'
-      return [true, i+1, j]
+    [true, i + 1, j]
-    when ">"
+  when '>'
-      if j == matrix[i].length-1
+    if j == matrix[i].length - 1
-        matrix[i][j] = "."
+      matrix[i][j] = '.'
       return [false, -1, -1]
     end
 
-      if matrix[i][j+1] == "#"
+    if matrix[i][j + 1] == '#'
-        matrix[i][j] = "v"
+      matrix[i][j] = 'v'
       return [true, i, j]
     end
 
-      matrix[i][j+1] = ">"
+    matrix[i][j + 1] = '>'
-      matrix[i][j] = "."
+    matrix[i][j] = '.'
-      return [true, i, j+1]
+    [true, i, j + 1]
-    when "<"
+  when '<'
     if j == 0
-        matrix[i][j] = "."
+      matrix[i][j] = '.'
       return [false, -1, -1]
     end
 
-      if matrix[i][j-1] == "#"
+    if matrix[i][j - 1] == '#'
-        matrix[i][j] = "^"
+      matrix[i][j] = '^'
       return [true, i, j]
     end
 
-      matrix[i][j-1] = "<"
+    matrix[i][j - 1] = '<'
-      matrix[i][j] = "."
+    matrix[i][j] = '.'
-      return [true, i, j-1]
+    [true, i, j - 1]
   end
 end
 
 def get_current_position(matrix)
-  for i in 0..matrix.length-1 do
+  for i in 0..matrix.length - 1 do
-    for j in 0..matrix[i].length-1 do
+    for j in 0..matrix[i].length - 1 do
-      if ['^', '>', 'v', '<'].include?(matrix[i][j])
+      return [i, j] if ['^', '>', 'v', '<'].include?(matrix[i][j])
-        return [i, j]
-      end
     end
   end
 
-  return []
+  []
 end
 
 def count_possible_obstructions(matrix)
@@ -95,35 +94,31 @@ def count_possible_obstructions(matrix)
   start_i, start_j = get_current_position(matrix)
   start_symbol = matrix[start_i][start_j]
 
-  for i in 0..matrix.length-1 do
+  for i in 0..matrix.length - 1 do
-    for j in 0..matrix[i].length-1 do
+    for j in 0..matrix[i].length - 1 do
-      if matrix[i][j] != "."
+      next if matrix[i][j] != '.'
-        next
-      end
 
-      matrix[i][j] = "#"
+      matrix[i][j] = '#'
-      if test_loop(matrix, start_i, start_j)
+      count += 1 if test_loop(matrix, start_i, start_j)
-        count += 1
+      matrix[i][j] = '.'
-      end
-      matrix[i][j] = "."
       matrix[start_i][start_j] = start_symbol
     end
   end
 
-  return count
+  count
 end
 
 def test_loop(matrix, i, j)
   should_continue = true
 
-  history = Hash.new
+  history = {}
 
-  while should_continue do
+  while should_continue
     symbol = matrix[i][j]
     key = "#{i},#{j},#{symbol}"
 
     if history.include?(key)
-      matrix[i][j] = "."
+      matrix[i][j] = '.'
       return true
     end
 
@@ -132,5 +127,5 @@ def test_loop(matrix, i, j)
     should_continue, i, j = make_step(matrix, i, j)
   end
 
-  return false
+  false
 end