how to change string that contain math operation and simbol into solveable statement in JavaScript

Question

For example :

Input :
var a = "("
var b = "2"
var c = "+"
var d = "5"
var e = ")"
var f = [a,b,c,d,e]

document.write(f.join(""))

And the output is "(2+5)"

But i want to make that the output is 7... I have tried using

parseInt(f.join("")) but the result still "(2+5)"

Which function should i use to solve those following string, thanks

Answer 1

There is no javascript function that parses the entire expression at once.
This is not an easy task that requires writing code.

https://medium.com/@stoopidguy1992/how-to-write-a-math-expression-parser-in-javascript-b5147bc9466b

Answer 2

function adding(x,y){
var x1= parseInt(x);
var y1 = parseInt(y);
return x1+y1;
}