function mask(f){
	tel='';
	var counter=0;
	val =f.value.split('');
	for(var i=0;i<val.length;i++){
		if(val[i].match(/\d/)){
			if(counter==2){val[i]=val[i]+'-'}
			if(counter==5){val[i]=val[i]+'-'}
			tel=tel+val[i]
			counter++;
		}
	}
	f.value=tel;
}