Calculator based on pratt parser
output
Supported Operators:
Prefix: +, -, ~(bitwise not)
Postfix: !(factorial)
Infix: +, -, *, /, %, <<,>>, &, |, ^, **(power)
Builtin functions: sin, cos, tan, log, abs, deg(degree to radian)
Builtin constants: PI, E
Number format: A(.B)? (eg. 3.3, 0.1, 3242)