map1={wallslength=4,wallsx={30,30,50,50},wallsy={30,50,50,30}}
map2={}
map3={}
s=0
sf=1

function _update()
 cls()
    s=1
    sf=2
    repeat
        if sf > map1.wallslength then
        line(map1.wallsx[s],map1.wallsy[s],map1.wallsx[1],map1.wallsy[1])
        else
     line(map1.wallsx[s],map1.wallsy[s],map1.wallsx[s+1],map1.wallsy[s+1])
     end
     s+=1
     sf+=1
    until s==map1.wallslength
end