[PKU] P3062: Celebrity jeopardy

It’s hard
to construct a problem that’s so easy that everyone will get it, yet
still difficult enough to be worthy of some respect. Usually, we err on
one side or the other. How simple can a problem really be?

Here, as in Celebrity Jepoardy, questions and answers are a bit
confused, and, because the participants are elebrities, there’s a real
need to make the challenges simple. Your program needs to prepare a
question to be solved — an equation to be solved — given the
answer. Specifically, you have to write a program which finds the
simplest possible equation to be solved given the answer, considering
all possible equations using the standard mathematical symbols in the
usual manner. In this context, simplest can be defined unambiguously
several different ways leading to the same path of resolution. For now,
find the equation whose transformation into the desired answer requires
the least effort.

For example, given the answer X = 2, you might create the equation
9 – X = 7. Alternately, you could build the system X > 0; X^2 = 4.
These may not be the simplest possible equations. Solving these
mind-scratchers might be hard for a celebrity.

Each input line contains a solution in the form <symbol> = <value>

For
each input line, print the simplest system of equations which would to
lead to the provided solution, respecting the use of space exactly as
in the input.