package seedu.emeraldo.logic.commands;

public class UndoCommand extends Command {

    public static final String COMMAND_WORD = "undo";
    public static final String MESSAGE_SUCCESS = "Undo successful!";

    public UndoCommand() {}
    
    @Override
    public CommandResult execute() {
        
        
        return new CommandResult(MESSAGE_SUCCESS);
    }

}

@@ -199,16 +199,94 @@
 ssful!%22;
+%0A    public static final String MESSAGE_UNSUCCESSFUL =  %22Cannot undo further%22;
 %0A%0A    pu

Add MESSAGE_UNSUCCESSFUL to UndoCommand