document.addEventListener('keydown', function(e){
KEY = ["t", "e", "s", "t"];
this.INPUT = this.INPUT || [];
this.INPUT.push(e.key);
if (this.INPUT.some((e, i) => KEY[i] != e))
this.INPUT = [this.INPUT.pop()];
else if (this.INPUT.length == KEY.length){
console.log("Congratulations!");
this.INPUT = [];
}
})