Create random maze using the spanning tree algorithm from "How to Build a Maze",
David Matuszek, Byte Magazine, vol.6, n.12, pp.190-196, December 1981,
https://archive.org/details/byte-magazine-1981-12

Download everything: newmaze.zip

create.c - create maze
draw.c - draw maze
maze.c - utility routines
maze.h - constants and datatypes

Use maze.sh to create and draw (gif) a maze and solution,
or draw.sh to draw (gif) from existing maze data.

See examples in data/

Any two edge cells can be used for the entrance and exit, but the code here
always uses the top left and bottom right cells.  After generating the spanning tree,
additional cell walls can be broken, which may make the maze harder to solve.

Manual examples using the C programs directly:

% cat data/m-2-4a.txt
2 4
 0 1  0 0  1 0  0 0
 1 1  0 1  0 1  1 1
% ./draw < data/m-2-4a.txt
 _______
 _  |   |
|_ _ _|_
% ./draw -x < data/m-2-4a.txt
XXXXXXXXXXXXXXXXXX
        XX      XX
XXXXXX  XX  XX  XX
XX          XX
XXXXXXXXXXXXXXXXXX
%
% ./create > j
% ./draw < j
% ./draw -x < j
% ./draw -g < j | ./mazeplot.sh > j.gif
% eog j.gif &
% ./draw -g -s < j > solve.out
% ./draw -g < j | ./solveplot.sh > j.gif
% 
% ./create > m-8-16.txt
% ./draw -g -s < m-8-16.txt > m-8-16-solve.txt
% ./draw -g < m-8-16.txt | ./solveplot.sh m-8-16-solve.txt > m-8-16-solve.gif