Поменять местами максимальный и минимальный элементы массива А(14)

CLS
n = 14
DIM a(n)
FOR i = 1 TO n
    PRINT "vvedite element"; i
    INPUT a(i)
NEXT
min = a(1): max = a(1)
FOR i = 1 TO n
    IF a(i) >= max THEN max = a(i): k1 = i
    IF a(i) <= min THEN min = a(i): k2 = i
NEXT
CLS
PRINT "massiv"
FOR i = 1 TO n
    PRINT a(i);
NEXT
PRINT
PRINT "max ="; max: PRINT "min ="; min
SWAP a(k1), a(k2)
FOR i = 1 TO n
    PRINT a(i);
NEXT

CLS
ny = 4: nx = 3
DIM b(ny, nx)
FOR y = 1 TO ny
    FOR x = 1 TO nx
        PRINT "vvedite element"; y; "stroka"; x; "stolbec"
        INPUT b(y, x)
    NEXT
NEXT
FOR y = 1 TO ny
    FOR x = 1 TO nx
        IF b(y, x) > 0 THEN s1 = s1 + b(y, x) ELSE s2 = s2 + b(y, x)
    NEXT
NEXT
PRINT "matrica"
FOR y = 1 TO ny
    FOR x = 1 TO nx
        PRINT b(y, x);
    NEXT
    PRINT
NEXT
PRINT
PRINT "summa polozhitelnyh = "; s1
PRINT "summa otrichatelnyh =  "; s2