class NoSuchStudentException(Exception):
    pass

class Garden:
    def __init__(self, diagram, students=None):
        self.diagram = diagram
        if students is None:
            self.students = [
                "Alena", "Boris", "Cyril", "Daniel", "Eva", "František", 
                "Gitka", "Helena", "Ivana", "Jozef", "Karol", "Ladislav"
            ]
        else:
            self.students = sorted(students)
            
        self.plant_names = {
            "G": "Tráva",
            "C": "Ďatelina",
            "R": "Reďkovky",
            "V": "Fialky"
        }

    def plants(self, student):
        if student not in self.students:
            raise NoSuchStudentException("Student not found")
            
        index = self.students.index(student)
        start = index * 2
        
        rows = self.diagram.splitlines()
        row1 = rows[0]
        row2 = rows[1]
        
        letters = row1[start:start+2] + row2[start:start+2]
        
        return [self.plant_names[char] for char in letters]