2620. Counter

Given an integer n, return a counter function. This counter function initially returns n and then returns 1 more than the previous value every subsequent time it is called (n, n + 1, n + 2, etc).

Example 1.

Input:
n = 10
["call","call","call"]
Output: [10,11,12]
Explanation:
counter() = 10 // The first time counter() is called, it returns n.
counter() = 11 // Returns 1 more than the previous time.
counter() = 12 // Returns 1 more than the previous time.

Example 2

Input:
n = -2
["call","call","call","call","call"]
Output: [-2,-1,0,1,2]
Explanation: counter() initially returns -2. Then increases after each sebsequent call.

Approach

Since the function is Closure, It memories the inner variable which is n by passing as parameter.

We need to add 1 to the passed parameter n by n ++ then, Every time function createCounter is called, number n is increasing by 1

How i Solved the Problem

/**
 * @param {number} n
 * @return {Function} counter
 */
var createCounter = function (n) {
  return function () {
    return n++;
  };
};