Data commit

Task/Cut-a-rectangle/Julia/cut-a-rectangle.julia

@@ -0,0 +1,68 @@
+const count = [0]
+const dir = [[0, -1], [-1, 0], [0, 1], [1, 0]]
+
+function walk(y, x, h, w, grid, len, next)
+    if y == 0 || y == h || x == 0 || x == w
+        count[1] += 2
+        return
+    end
+    t = y * (w + 1) + x
+    grid[t + 1] += UInt8(1)
+    grid[len - t + 1] += UInt8(1)
+    for i in 1:4
+        if grid[t + next[i] + 1] == 0
+            walk(y + dir[i][1], x + dir[i][2], h, w, grid, len, next)
+        end
+    end
+    grid[t + 1] -= 1
+    grid[len - t + 1] -= 1
+end
+
+function cutrectangle(hh, ww, recur)
+    if isodd(hh)
+        h, w = ww, hh
+    else
+        h, w = hh, ww
+    end
+    if isodd(h)
+        return 0
+    elseif w == 1
+        return 1
+    elseif w == 2
+        return h
+    elseif h == 2
+        return w
+    end
+    cy = div(h, 2)
+    cx = div(w, 2)
+    len = (h + 1) * (w + 1)
+    grid = zeros(UInt8, len)
+    len -= 1
+    next = [-1, -w - 1, 1, w + 1]
+    if recur
+        count[1] = 0
+    end
+    for x in cx + 1:w - 1
+        t = cy * (w + 1) + x
+        grid[t + 1] = 1
+        grid[len - t + 1] = 1
+        walk(cy - 1, x, h, w, grid, len, next)
+    end
+    count[1] += 1
+    if h == w
+        count[1] *= 2
+    elseif iseven(w) && recur
+        cutrectangle(w, h, false)
+    end
+    return count[1]
+end
+
+function runtest()
+    for y in 1:10, x in 1:y
+        if iseven(x) || iseven(y)
+            println("$y x $x: $(cutrectangle(y, x, true))")
+        end
+    end
+end
+
+runtest()