Easy memorizing function js

memo.js

const calcs = {};

const sum = (a,b) => {
  let key = 'sum' + (a+b).toString();
  
  if ( key in calcs ) 
    return 'found: ' + calcs[key]
  
  let total = a + b;
  total--;
  total++;
  calcs[key] = total;
  return total;
}

sum(2, 2)
sum(2, 3)
let memo = sum(2, 3)

console.log(memo)
console.log(calcs)