Write a program that lets you know if you can have a key or not, based on your role at the school.
 First ask for the user’s role at the school. They can be a student, administrator, or a teacher. (And remember that capitalization is important! ‘Student’ is not the same as ‘student’.)
 Example 1: Administrator or Teacher
 For example, if this was the input:
 Are you an administrator, teacher, or student?: teacher
 This should be the output:
 Administrators and teachers get keys!
 Example 2: Student
 And if this was the input:
 Are you an administrator, teacher, or student?: student
 This should be the output:
 Students do not get keys!
 (Note: You should also be able to handle a situation where the user enters a value other than administrator, teacher or student and tell them they must be one of the three choices!)
 Example 3: Other
 If they input anything else:
 Are you an administrator, teacher, or student?: secretary
 This should be the output:
 You can only be an administrator, teacher, or student!
   
Ответ:
Розкладемо число 50 на степені двійки, починаючи з найбільшого можливого:
50 = 32 + 16 + 2
Записуємо отримані степені двійки у вигляді двійкових чисел:
32 = 100000
16 = 10000
2 = 10
Сумуємо двійкові числа, щоб отримати результат:
50 (10) = 110010 (2)
Отже, число 50 в двійковій системі числення буде записуватись як 110010.