Longest Sub Array

longestarray.js

//O(n^2) way
function maxLength(a, k) {
    // Write your code here
    var _arr = [];
    for (var i = 0; i <= a.length; i++) {
        for (var j = i + 1; j <= a.length; j++) {
            console.log(j - i, _arr.length && a.slice(i, j).reduce((a, b) => a + b, 0) <= k)
            if (j - i > _arr.length && a.slice(i, j).reduce((a, b) => a + b, 0) <= k) {
                _arr = a.slice(i, j);
            }
        }
    }
    return _arr.length;
}



//Efficient Way
var subarraySum = function(nums, k) {
        
  let count = 0;
  let sum = 0;
  let hash = {};
  
  for(let i = 0; i < nums.length; i++) {
      
    sum += nums[i];
    
    count += (sum === k) ? 1 : 0;
    
    count += ((sum - k) in hash) ? hash[sum-k] : 0
    
    hash[sum] = (sum in hash) ? hash[sum] + 1 : 1;
      
  }
    
  return count;
    
};