CODE EXAMPLE FOR PYTHON

Delete occurrences of an element if it occurs more than n times

/*
Given a list and a number, create a new list that contains each number of list at 
	most N times, without reordering.
For example if the input number is 2, and the input list is [1,2,3,1,2,1,2,3], 
	you take [1,2,3,1,2], drop the next [1,2] since this would lead to 1 and 2 
    being in the result 3 times, and then take 3, which leads to [1,2,3,1,2,3].
With list [20,37,20,21] and number 1, the result would be [20,37,21].
*/

const deleteNth = (arr,n) => {
  let numCount = {}, occElem = []
  
  arr.forEach(num => {
    if(numCount[num] === undefined) numCount[num] = 0
    if(numCount[num] === n) return null
    else{
      occElem.push(num)
      numCount[num] += 1
     }
  })
  return occElem
}

// With love @kouqhar