statement.md

Find x

Problem description

Implement a simple equation solver to evaluate expressions consisting of numbers, variables, addition, and subtraction operators.

Input

Input consists of at most 100 equations, each on a line of its own.

Each equation contains one unknown identified by a lowercase letter. The unknown will be located in either the right or left-hand side of the equation.

Terms of the equations are separated by spaces. If a term is signed, there will be no space between the term and its sign.

The numbers that appear in the equations have an absolute value less than 100.

Output

For each equation, ouput a line in the form:

<var> = <value>

where <var> is the name of the unknown in the equation, and <value> is the solution to the equation.

Sample input

+4 - +5 - x  = 2
-4 -  5 - y  = 2
+4 - -5 - z  = 2
-4 -  5 = -a + 2
+4 -  5 = +d + 2

Sample output

x = -3
y = -11
z = 7
a = 11
d = -3

Generate test cases

The script generator.py can be used to generate test data. Just run:

python generator.py > in.txt