Data commit

Task/Langtons-ant/UNIX-Shell/langtons-ant.sh

@@ -0,0 +1,38 @@
+function main {
+  typeset -i width=$(tput cols)
+  typeset -i height=$(tput lines)
+  typeset -a grid
+  typeset -i i
+  for (( i=0; i<height; ++i )); do
+    grid+=("$(printf "%${width}s" ' ')")
+  done
+  typeset -i x=$(( width / 2 )) y=$(( height / 2 ))
+  (( dx=0, dy = 1 - 2*RANDOM%2 ))
+  if (( RANDOM % 2 )); then
+    (( dy=0, dx = 1 - 2*RANDOM%2 ))
+  fi
+  printf '\e[H';
+  printf '%s\n' "${grid[@]}"
+  tput civis
+  while (( x>=0 && x < width && y >=0 && y< height)); do
+     (( i=y ))
+     if [[ -n $ZSH_VERSION ]]; then
+        (( i += 1 ))
+     fi
+     ch=${grid[i]:$x:1}
+    if [[ $ch == '#' ]]; then
+      (( t=dx, dx=dy, dy=-t ))
+      grid[i]=${grid[i]:0:$x}' '${grid[i]:$x+1}
+    else
+      (( t=dx, dx=-dy, dy=t ))
+      grid[i]=${grid[i]:0:$x}'#'${grid[i]:$x+1}
+    fi
+    (( x += dx, y += dy ))
+    tput cup $y 0 && printf '%s' "${grid[i]}"
+  done
+  tput cnorm
+  read line
+  return
+}
+
+main "$@"