function valid_form(f){
	var error = "";
	/*
	if (f.weight.value=="0" || f.weight.lenght<1) { 
		error += "Your weight is required.\n";
	}
	
	
	if (f.monitored.value=="0" || f.monitored.lenght<1) { 
		error += "Your monitored is required.\n";
	}
	
	if (f.distance.value=="0" || f.distance.lenght<1) { 
		error += "Your distance is required.\n";
	}
	*/
	if (f.nom.value=="" || f.nom.lenght<1) { 
		error += "Your name is required.\n";
	}
	if (f.prenom.value=="" || f.prenom.lenght<1) { 
		error += "Your first name is required.\n";
	}
	if (f.tel.value=="" || f.tel.lenght<1) { 
		error += "Your phone number is required.\n";
	}
	if (f.mail.value=="" || f.mail.lenght<1) { 
		error += "Your email is required.\n";
	}
	
	error += f.verif.value.length > 0 && f.verif.value!='' ? "" : "Verification code\n";
	
	if(error != ""){
		alert(error);
		return false;
	}else{
		return true;
	}
}