Add multiple cookies from string

string_to_cookies.js

var str = "a=b; c=d;";

var addCookies(str) {
  var multiple = res.split(";");

  for(var i=0; i<multiple.length; i++) {  
    var key = multiple[i].split("=");
    document.cookie=key[0] + "=" + key[1];  
  }
};

addCookies(str)