SCREEN 9
COLOR , 1
X = 300: Y = 200: C = 2
PRINT "Для выхода нажмите <Esc>; для стирания <z>, для рисования <c>, а потом <a>(влево); <s>(вверх); <d>(вправо); <x>(вниз)."
1 : PSET (X, Y), C
K$ = INKEY$
IF K$ = "" THEN 1
SELECT CASE K$
        CASE IS = "a"
                GOTO L
        CASE IS = "d"
                GOTO R
        CASE IS = "s"
                GOTO U
        CASE IS = "x"
                GOTO D
        CASE IS = "z"
                GOTO C
        CASE IS = "c"
                GOTO DR
        CASE IS = CHR$(27)
                GOTO E
        CASE ELSE
                GOTO 1
END SELECT
E: END
U: Y = Y - 1
GOTO 1
L: X = X - 1
GOTO 1
R: X = X + 1
GOTO 1
D: Y = Y + 1
GOTO 1
DR: C = 2
GOTO 1
C: C = 1
GOTO 1