var input = 7;

var elves = [];
for(var i = 0; i < input; i++){
	elves.push(i+1);
}

var i = 0;
while(elves.length > 1){
	if(!(elves.length%1000)) console.log(elves.length)
	var toRemove = Math.floor((i + (elves.length/2)))%(elves.length)
	//console.log(i, elves[i], elves[toRemove], elves);
	elves.splice(toRemove, 1);
	if(toRemove > i){
		i = (i+1)%elves.length;
	}
	else{
		i = i%elves.length;
	}
}

console.log(elves);