Whats better javascript OOP notation?

maximum.js

var Maximum = function(array) {
  this.array = array;
  
  this.findMax = function (){
    var maxValue = 0;
    this.array.forEach(function(n) {
      if (maxValue < n)
      {
       maxValue = n;
      }
    });
    return maxValue;
  };
};

//or

function Maximum(array) {
  this.array = array;

  this.findMax = function (){
    var maxValue = 0;
    this.array.forEach(function(n) {
      if (maxValue < n)
      {
       maxValue = n;
      }
    });
    return maxValue;
  };

}

//Either way you call it the same
var person = new Minimum(ages);
person.findMax();