k0 = 0

FORALL ( i=1:n, j=1:m )

x(i,j) = CMPLX((i-1)*1.0/(n-1),(j-1)*1.0/(m-1))

k(i,j) = 0

xtmp(i,j) = 0

mask(i,j) = .TURE.

END FORALL

DO WHILE (ANY(mask(1:n,1:m)) .AND. k0<1000)

FORALL ( i=1:n, j=1:m, mask(i,j))

xtmp(i,j) = xtmp(i,j)*xtmp(i,j)-x(i,j)

k(i,j) = k(i,j) + 1

mask(i,j) = ABS(xtmp(i,j))<2.0

END FORALL

k0 = k0 + 1

END DO