linear-time min/max helper functions for arrays of numbers

minmax.js

// time:  O(n)
// space: O(1)
var max = function(arr) {
  var returnable = Number.MIN_VALUE;
  arr.forEach(function(v){
    if(returnable < v) {
      returnable = v;
    }
  })
  return returnable;
}

var min = function(arr) {
  var returnable = Number.MAX_VALUE;
  arr.forEach(function(v){
    if(returnable > v) {
      returnable = v;
    }
  })
  return returnable;
}