get only two letter from any string

Shell Programming and Scripting
1

I want get middle two latter of any string.

Input:
var="070108"

output:

var1="01"

please help.

2

Using sed, assuming it contains 6 numbers,

using bash,

3

[zsh]

% v=070108
% print $v[$#v/2,$#v/2+1]
01
% v=abcd
% print $v[$#v/2,$#v/2+1]
bc
% v=12345678910
% print $v[$#v/2,$#v/2+1]
56

[bash]

echo ${v:(${#v}/2)-1:2}