Common elements in two arrays javascript

arrNum1 = new Array(1,2,3);
arrNum2 = new Array(2,3,4,5);
arrNum3 = new Array();

arrNum3 =  intersect_safe(arrNum1, arrNum2);

for(i=0;i<arrNum3.length;i++)
 alert(arrNum3[i]);

function intersect_safe(a, b)
{
  var ai=0, bi=0;
  var result = new Array();

   while(ai<a.length && bi < b.length )
  {
     if(a[ai] != b[bi])
     { 
       bi++; 
     }
     else
     {
       result.push(a[ai]);
       ai++;
       bi++;
     }
  }

  return result;
}

  var arr = [1,2,3,4];  

Method 1:

var total = 0;
$.each(arr,function() {
    total += this;
});

Method 2:

  var sum = eval(arr.join('+'));

Method 3:

  var i = arrMaxInvst.length;
  var sum = 0;
 
  while (--i) 
   sum += arrMaxInvst[i];

var arr = new Array();
arr[0] = 100;
arr[1] = 0;
arr[2] = 50;

Array.prototype.max = function() {
  return Math.max.apply(null, this)
}

Array.prototype.min = function() {
  return Math.min.apply(null, this)
}

var min = Math.min.apply(null, arr),
    max = Math.max.apply(null, arr);

To find the Maximum value in Array Use Below

 var max_of_array = Math.max.apply(Math, array);