public void edit(int index, String subject, String text, int priority) {
		if(index<0 || index==this.size()) { // Reveals if the number exists
			return;
		}
		boolean a;
		for(int i = 0; i<this.size(); ++i) {
			a = true;
			for(int j = 0; j<this.size(); ++j) { // Makes the subject unique
				if(subject.equals(get(j).getSubject())) {
					subject += " ";
					a = false;
				}
			}
			if(a) { // If the subject is unique, continue with program
				get(index).setSubject(subject);
				get(index).setText(text);
				get(index).setPriority(priority);
				get(index).changeDate();
				return;
			}
		}
	}