text: /*
  1343. Number of Sub-arrays of Size K and Average Greater than or Equal to Threshold
  Medium
  
  418
  
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  Given an array of integers arr and two integers k and threshold.
  
  Return the number of sub-arrays of size k and average greater than or equal to threshold.
  
  
  
  Example 1:
  
  Input: arr = [2,2,2,2,5,5,5,8], k = 3, threshold = 4
  Output: 3
  Explanation: Sub-arrays [2,5,5],[5,5,5] and [5,5,8] have averages 4, 5 and 6 respectively. All other sub-arrays of size 3 have averages less than 4 (the threshold).
  */
  
  //O(N) time and O(1) space
  var numOfSubarrays = function(arr, k, threshold) {
    var count = 0;
    var start = 0;
    var currSum = 0;
    for (var end = 0; end < arr.length; end++) {
        currSum+=arr[end];
  
        if (end-start+1 === k) {
            if (currSum/k >= threshold) {
                count++;
            }
            currSum-=arr[start];
            start++;
        }
  
    }
  
    return count;
  };
  