The symbol [ ] denotes the greatest integer function:
$[x] = \text{greatest integer less than or equal to }x .$
If $m$ is an integer, find each of the following limits. If the limit does not exist, enter DNE below.

(a) $\displaystyle \lim_{x \to -3^+} [x]$ =
(b) $\displaystyle \lim_{x \to -3} [x]$ =
(c) $\displaystyle \lim_{x \to -2.4} [x]$ =
(d) $\displaystyle \lim_{x \to m^-} [x]$ =
(e) $\displaystyle \lim_{x \to m^+} [x]$ =
(f) $\displaystyle \lim_{x \to m} [x]$ =