From b4ff6798cdec6c9bd837b4da69e9c7a0b0d9eb24 Mon Sep 17 00:00:00 2001
From: Renaud Fivet <renaud.fivet@gmail.com>
Date: Fri, 19 May 2017 11:19:13 +0800
Subject: [PATCH] Seed the pseudo-random generator on initialization. Add
 example script to solve a maze by flood painting.

---
 eval.c       |  3 +++
 floodmaz.cmd | 63 ++++++++++++++++++++++++++++++++++++++++++++++++++++
 maze.cmd     |  9 ++++++++
 3 files changed, 75 insertions(+)
 create mode 100644 floodmaz.cmd

diff --git a/eval.c b/eval.c
index 379bf0c..842280c 100644
--- a/eval.c
+++ b/eval.c
@@ -13,6 +13,7 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <time.h>
 
 #include "basic.h"
 #include "bind.h"
@@ -305,6 +306,8 @@ void varinit(void)
 		result = malloc( NSTRING) ;
 		ressize = NSTRING ;
 	}
+
+	seed = time( NULL) ;
 }
 
 /*
diff --git a/floodmaz.cmd b/floodmaz.cmd
new file mode 100644
index 0000000..23f0a5b
--- /dev/null
+++ b/floodmaz.cmd
@@ -0,0 +1,63 @@
+# 6 set $seed
+execute-file maze.cmd
+
+set %thisbuf $cbufname
+
+10 store-macro				# push x y
+	set %x $curcol
+	set %y $curline
+	select-buffer stack
+	beginning-of-file
+	insert-string %x
+	newline
+	insert-string %y
+	newline
+	select-buffer %thisbuf
+!endm
+
+11 store-macro				# pop x y
+	select-buffer stack
+	beginning-of-file
+	set %x $line
+1	kill-to-end-of-line
+	set %y $line
+1	kill-to-end-of-line
+	select-buffer %thisbuf
+	set $curline %y
+	set $curcol %x
+!endm
+
+set $curline 1
+set $curcol 0
+execute-macro-10	#push stop position
+set %x 1
+set $curline 4
+set $curcol %x
+set %OC $curchar
+set %NC &asc "█"
+!while &not &equ %x 0
+	set $curchar %NC
+	set %cc $curcol
+	set %ll $curline
+	set $curcol &add %cc 1
+	!if &equ $curchar %OC
+		execute-macro-10
+	!endif
+	set $curcol &add %cc -1
+	!if &equ $curchar %OC
+		execute-macro-10
+	!endif
+	set $curline &add %ll 1
+	set $curcol %cc
+	!if &equ $curchar %OC
+		execute-macro-10
+	!endif
+	set $curline &add %ll -1
+	set $curcol %cc
+	!if &equ $curchar %OC
+		execute-macro-10
+	!endif
+	execute-macro-11	
+!endwhile
+set $curline 3
+set $curcol 1
diff --git a/maze.cmd b/maze.cmd
index ea02483..8e5f519 100644
--- a/maze.cmd
+++ b/maze.cmd
@@ -1,4 +1,7 @@
+# record seed
 # 5 set $seed
+set %S $seed
+
 # setup direction offsets
 set %D1 0
 set %D2 1
@@ -83,6 +86,12 @@ set %cnt &tim &sub &div %w 2 1 &sub &div %l 2 1
 	set $curcol %x
 !endwhile
 
+# id maze
+beginning-of-file
+kill-to-end-of-line
+insert-string &cat " Maze " &cat %w &cat "x" &cat &sub %l 2 &cat " #" %S
+&sub $curwidth $curcol insert-string " "
+
 # draw the entrance
 set $curline 3
 set $curcol 1