Problems
Value of expression 1
Value of expression 1
Compute the value of the expression for the given real numbers $x$ and $y$.
$$
2x^2 - 4xy + 3y^2 + {x + y \over 7}
$$
\InputFile
Two real numbers $x$ and $y$.
\OutputFile
Print the value of the given expression with precision to the thousandths.
Input example #1
1.000 -2.000
Output example #1
21.857