[0]  # perl parameter_check.pl -ddd  -c -b
b is zero length string or equivalent
option c:1
option d: dd


[0]  # perl parameter_check.pl -ddd   -b -c
option b: -c
Use of uninitialized value in say at parameter_check.pl line 18.
option c:
option d: dd

[0]  # perl parameter_check.pl -ddd -b -c
option b -c
Use of uninitialized value in say at parameter_check.pl line 18.
option c:
option d: dd

[0]  # perl parameter_check.pl -ddd  -c -b --
option b --
option c:1
option d: dd

[0]  # perl parameter_check.pl -c -b -ddd
option b -ddd
option c:1
Use of uninitialized value in say at parameter_check.pl line 19.
option d: