Frequency distribution of elements - JavaScript

We are required to write a JavaScript function that contains the following string −

const str = 'This string will be used to calculate frequency distribution';

We need to return an object that represents the frequency distribution of various elements present in the array.

Example

Following is the code −

const str = 'This string will be used to calculate frequency
distribution';
const frequencyDistribution = str => {
   const map = {};
   for(let i = 0; i < str.length; i++){
      map[str[i]] = (map[str[i]] || 0) + 1;
   };
   return map;
};
console.log(frequencyDistribution(str));

Output

Following is the output in the console −

{
   T: 1,
   h: 1,
   i: 6,
   s: 4,
   ' ': 8,
   t: 5,
   r: 3,
   n: 3,
   g: 1,
   w: 1,
   l: 4,
   b: 2,
   e: 5,
   u: 4,
   d: 2,
   o: 2,
   c: 3,
   a: 2,
   f: 1,
   q: 1,
   y: 1
}