Дан массив B(2,4). Вычислить произведение p положительных элементов. Вывести на экран B(2,4) и p — QBasic(Бейсик)

DIM b(2, 4)
FOR i = 1 TO 2
    FOR j = 1 TO 4
        PRINT "vvedite element b("; i; ","; j; ")=";
        INPUT b(i, j)
    NEXT
NEXT
PRINT "massiv"
FOR i = 1 TO 2
    FOR j = 1 TO 4
        PRINT b(i, j);
    NEXT
    PRINT
NEXT
p = 1
FOR i = 1 TO 2
    FOR j = 1 TO 4
        IF b(i, j) > 0 THEN p = p * b(i, j): f = 1
    NEXT
NEXT
IF f = 1 THEN PRINT "proizvedenie polijitelnyh="; p ELSE PRINT "polojitelnyh net"