students = {
    'Alice': {
         'Mathematiques': 90,
         'Francais': 80,
         'Histoire': 95
    },
    'Bob': {
         'Mathematiques': 75,
         'Francais': 85,
         'Histoire': 70
    },
     'Charlie': {
         'Mathematiques': 88,
         'Francais': 92,
         'Histoire': 78
     }
}

name = input("Entrez le nom de l'étudiant : ")
if name in students:
    total = 0
    print(f"Notes de {name}:")
    for i in students[name]:
        note = students[name][i]
        total += note
        print(i, ":", note)
    print(f"Moyenne de {name} : {total/len(students[name])}")

else:
    print("L'étudiant", name, "n'existe pas.")