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Problemwhether

Problemwhether is not a standard technical term in most formal literature, but it is sometimes used informally to denote a class of decision problems posed as yes/no questions. In this sense, a problemwhether asks, given an input, whether a particular property holds.

Formally, if P is a property of objects from a domain D, the problemwhether P takes input

Examples include problemwhether n is prime, problemwhether a graph is connected, or problemwhether a string belongs

In practice, the phrase reflects the linguistic notion of forming a yes/no question with the word “whether.”

Overall, the concept centers on deciding the truth of a given property for inputs, a cornerstone of

x
in
D
and
outputs
true
if
P(x)
is
true
and
false
otherwise.
Equivalently,
it
is
the
decision
problem
associated
with
the
language
L
=
{
x
in
D
:
P(x)
}.
The
study
of
such
problems
concerns
decidability,
complexity,
and
efficiency
of
determining
the
truth
of
P
for
arbitrary
inputs.
to
a
given
formal
language.
These
illustrate
the
typical
yes/no
questioning
structure:
given
an
instance,
determine
whether
the
property
holds.
This
contrasts
with
search
problems,
which
require
producing
a
witness
or
solution,
and
with
optimization
problems,
which
seek
best
or
extreme
values.
In
logic
and
computer
science,
these
questions
are
usually
treated
as
decision
problems
and
encoded
as
languages
to
study
their
computability
and
complexity
properties.
The
term
“problemwhether”
is
not
universally
standardized,
so
many
authors
prefer
formulations
like
“the
problem
of
deciding
whether
P(x)”
or
“the
decision
problem
for
P.”
decision
problems
in
theoretical
computer
science
and
logic.