String.prototype.ucfirst = function(){
	return this.slice(0,1).toUpperCase() + this.slice(1);
};

Number.prototype.number_format = function(){
　var num = new String(this).replace(/,/g, "");
　while(num != (num = num.replace(/^(-?\d+)(\d{3})/, "$1,$2")));
　return num;
}