import IO;
import util::Math;
import List;

public void make_maze(int w, int h){
	vis = [[0 | _ <- [1..w]] | _ <- [1..h]];
	ver = [["|  "| _ <- [1..w]] + ["|"] | _ <- [1..h]] + [[]];
	hor = [["+--"| _ <- [1..w]] + ["+"] | _ <- [1..h + 1]];

	void walk(int x, int y){
		vis[y][x] = 1;

		d = [<x - 1, y>, <x, y + 1>, <x + 1, y>, <x, y - 1>];
		while (d != []){
			<<xx, yy>, d> = takeOneFrom(d);
			if (xx < 0 || yy < 0 || xx >= w || yy >= w) continue;
			if (vis[yy][xx] == 1) continue;
			if (xx == x) hor[max([y, yy])][x] = "+  ";
			if (yy == y) ver[y][max([x, xx])] = "   ";
			walk(xx, yy);
			}
 	}
 	
	walk(arbInt(w), arbInt(h));
	for (<a, b> <- zip(hor, ver)){
		println(("" | it + "<z>" | z <- a));
		println(("" | it + "<z>" | z <- b));
	}
}