subArray.js

/* given an array and value as k find if there is a subarray with sum = k */

function  findSubArray (arr, k) {
	var sumArr = []
  var sum = 0
  for(var i=0;i<arr.length;i++) {
  	sum += arr[i]
    if (sum === k) {
    	return [0, i]
    }
    sumArr.push(sum)
  }
  var map = {}
  for(i=0;i<sumArr.length;i++) {
  	if (typeof map[sumArr[i] -k] !== 'undefined') {
    	return [map[sumArr[i] - k ] + 1, i]
    }
    map[sumArr[i]] = i
  }
  return -1
}

console.log(findSubArray([1, 4, 3], 5))