Question

How can i quit this python program.

#********************************************************************************
#Program : SearchClassInfo.py

#Description: This program will ask a user to enter 6 courses and will allow him
# to search a class by course number, room number, intructor or time,
# the program will run until the user stop it.
#********************************************************************************
from os import sys
def main():
#Definition of 4 lists
courses = []
rooms = []
instructors = []
times = []
#Allow user to enter six courses
for x in range(2):
Course_Number =input('Enter the course number: ')
Room_Number = input('Enter a room number: ')
Instructor =input('Enter the Instructor of the course: ')
Time = input('Enter the time the course meets: ')
#Add elements in appriate list.
courses.append(Course_Number)
rooms.append(Room_Number)
instructors.append(Instructor)
times.append(Time)


loop = 1 #initialisation of a flag.

while loop != 0:
try:
#Display a menu of four choices to make to search a class.
print('\nEnter 1 to search by course number: ')
print('Enter 2 to search by room number: ')
print('Enter 3 to search by instructor: ')
print('enter 4 to search by time: ')

choice = int(input('Enter your choice: '))#ask user to enter his choise for search.

if choice == 1 :
#ask user to enter course number for search of corresponding elements.
Course_Number = input('Enter a course number: ')
if Course_Number in courses: #verify if the couse number entered is in the list
#extract the index of the course number in list.
i=courses.index(Course_Number)
#printing elements on the same index as course number in other lists.
print('\nThe detail for course',courses[i], 'are:'
'\nRoom:', rooms[i],
'\nInstructor:',instructors[i],
'\nTime:',times[i], end=' ''\n')
else:#message to alerte when course number does not exit
print('\nThis course number is not on schedule')
  
elif choice == 2 :
# #ask user to enter room number for search of corresponding elements.
Room_Number = input('Enter a room number: ')
if Room_Number in rooms:#verify if the room number entered is in the list
#extract the index of the room number in list.
i=rooms.index(Room_Number)
#printing elements on the same index as room number in other lists.
print('\nThe detail for course',courses[i], 'are:'
'\nRoom:', rooms[i],
'\nInstructor:',instructors[i],
'\nTime:',times[i], end=' ' '\n')
else:#message to alerte when room number does not exit
print('\nThis room number is not on schedule')

elif choice == 3 :
Instructor = input('Enter the Instructor of the course: ')
if Instructor in instructors:
i=instructors.index(Instructor)
print('\nThe detail for course',courses[i], 'are:'
'\nRoom:', rooms[i],
'\nInstructor:',instructors[i],
'\nTime:',times[i], end=' ' '\n')
else:
print('\nThis instructor is not on schedule')
  
elif choice == 4 :
Time = input('Enter the time the course meets: ')
if Time in times:
i=times.index(Time)
print('\nThe detail for course',courses[i], 'are:'
'\nRoom:', rooms[i],
'\nInstructor:',instructors[i],
'\nTime:',times[i], end=' ' '\n')
else:
print('\nThis time is not on schedule')
  
elif choice!=' ':
print('Choice goes from 1--->4')
loop = 0
  


print('\nDo you want to continue? Enter y for yes')
control = input(' ')

if control == 'y'or'Y':
loop = 1

elif control!=' ':
sys.exit(0)

except:
print('incorrect choice, must be 1,2,3 or4')
pass
  
main()

Answer 1

The code in image:

The code in the text:

from os import sys
def main(): #Definition of 4 lists
   courses = []
   rooms = []
   instructors = []
   times = [] #Allow user to enter six courses
   for x in range(2):
       Course_Number =input('Enter the course number: ')
       Room_Number = input('Enter a room number: ')
       Instructor =input('Enter the Instructor of the course: ')
       Time = input('Enter the time the course meets: ') #Add elements in appriate list.
       courses.append(Course_Number)
       rooms.append(Room_Number)
       instructors.append(Instructor)
       times.append(Time)
   loop = 1 #initialisation of a flag.
   while loop!=0:
       try: #Display a menu of four choices to make to search a class.
           print('\nEnter 1 to search by course number: ')
           print('Enter 2 to search by room number: ')
           print('Enter 3 to search by instructor: ')
           print('enter 4 to search by time: ')
           choice = int(input('Enter your choice: '))#ask user to enter his choise for search.
           if choice == 1 : #ask user to enter course number for search of corresponding elements.
               Course_Number = input('Enter a course number: ')
               if Course_Number in courses: #verify if the course number entered is in the list#extract the index of the course number in list.
                   i=courses.index(Course_Number) #printing elements on the same index as course number in other lists.
                   print('\nThe detail for course',courses[i], 'are:''\nRoom:', rooms[i],'\nInstructor:',instructors[i],'\nTime:',times[i], end=' ''\n')
               else:#message to alerte when course number does not exit
                   print('\nThis course number is not on schedule')
           elif choice == 2 : # #ask user to enter room number for search of corresponding elements.
               Room_Number = input('Enter a room number: ')
               if Room_Number in rooms: #verify if the room number entered is in the list #extract the index of the room number in list.
                   i=rooms.index(Room_Number) #printing elements on the same index as room number in other lists.
                   print('\nThe detail for course',courses[i], 'are:''\nRoom:', rooms[i],'\nInstructor:',instructors[i],'\nTime:',times[i], end=' ' '\n')
               else:#message to alerte when room number does not exit
                   print('\nThis room number is not on schedule')
           elif choice == 3 :
               Instructor = input('Enter the Instructor of the course: ')
               if Instructor in instructors:
                   i=instructors.index(Instructor)
                   print('\nThe detail for course',courses[i], 'are:''\nRoom:', rooms[i],'\nInstructor:',instructors[i],'\nTime:',times[i], end=' ' '\n')
               else:
                   print('\nThis instructor is not on schedule')
           elif choice == 4 :
               Time = input('Enter the time the course meets: ')
               if Time in times:
                   i=times.index(Time)
                   print('\nThe detail for course',courses[i], 'are:''\nRoom:', rooms[i],'\nInstructor:',instructors[i],'\nTime:',times[i], end=' ' '\n')
               else:
                   print('\nThis time is not on schedule')
           elif choice!=' ':
               print('Choice goes from 1--->4')
              
          
           print('\nDo you want to continue? Enter y for yes and n for no')
           control = input(' ')
          
           if control == 'y'or control=='Y':
               loop = 1
           elif control == 'N' or control=='n':
               loop=0
       except:
           print('incorrect choice, must be 1,2,3 or4')
           pass
      
  
main()

Output:

I just changed the condition in elif, so if the user enters n for no then the loop=0 and the while loop will be stopped.

I tried sys.exit() but it didn't worked for me.

If you have any doubt comment me.