The goal today is to write a function that evaluates a string that contains an arithmetic expression. We will do this by writing an calc function that calculates the expression using a stack.
For example:
- calc("1 + 2 * (20 / 5 )") -> 9
- calc("1 + 2 - 3") -> 0
- calc("1 + 3 + ( ( 4 / 2 ) * ( 8 * 4 ) )") -> 68
See https://medium.freecodecamp.com/zipline-build-a-smart-javascript-calculator-65e21a8b0b0c for additional guidance.
Write the calc function
