Very common problem in computational programming is to determine the underlying law to which some phenomenon obeys. For learning purpose let us practice a simple variant - discovering linear dependence by two given observations (for example, how the price for some product depends on its size, weight etc.)
Linear function is defined by an equation:
y(x) = ax + b
Where a
and b
are some constants.
For example, with a=3, b=2
function will yield values y = 2, 5, 8, 11...
for x = 0, 1, 2, 3...
Your task is to determine a
and b
by two points, belonging to the function.
I.e. you are told two pairs of values (x1, y1), (x2, y2)
which satisfy the function equation
- and you should restore the equation itself.
Input data have the number of test-cases in the first line
and then test-cases themselves in separate lines.
Each case contains 4
integers (x1 y1 x2 y2
).
Answers should be integer too and you are to write them in line, separating with spaces and enclosing each pair in parenthesis, for example:
input data:
2
0 0 1 1
1 0 0 1
answer:
(1 0) (-1 1)