CODEWITHSUNDEEP
pythonpython-3.x
MystIc Ace
MystIc Ace

Reputation: 3

how to stop loop in python?

i want to program that take user input line:, and check that each line is correct or not from a speech.txt. if the line is correct with line in file it should proceed and ask input again line: check the line again, if the line is wrong print the correct line, and if the user types LINE! then print the correct line from file, and print GOOD when lines finished. so FAR i have made this program but the last some loops are useless even if the lines in file are finished

f=open('speech.txt')
while True:
    userline=input("line: ")
    for line in f:
        line=line.strip()
        if line.lower() == userline.lower():
            userline=input("line: ")
        elif userline=="LINE!":
            print(line)
    print("Good!")
    break

Upvotes: 0

Views: 2422

Answers (4)

Odai Al-Ghamdi
Odai Al-Ghamdi

Reputation: 302

To stop a loop you should use: Break.

Upvotes: 0

Henry Keiter
Henry Keiter

Reputation: 17168

It seems to me like you're using more loops than you need. This is how I'd write it, if I understand your constraints correctly.

with open('speech.txt') as f:
    for line in f:
        line = line
        userline = input("line: ")
        if userline == 'LINE!':
            print(line)
        elif userline.strip().lower() == line.strip().lower():
            continue # Correct, so go on to the next line of the file
        else:
            print("Nope! Correct was:")
            print(line)
    print('FINISHED') # I wouldn't use "GOOD" unless the user gets everything right!

The trick here is the continue statement. This skips ahead to the next iteration of the loop if the user was correct. To break out of a loop entirely (say, if you wanted to simply stop when the user gets a line wrong), you would use the break statement.

I don't know what your original while loop was intended to do, but it wasn't doing anything at all in your code, and you don't need two loops just to go through a file once.

Upvotes: 0

Gabriel Samfira
Gabriel Samfira

Reputation: 2775

If I understood your question right, this would be what you are looking for:

try:
    _input = raw_input
except:
    _input = input

with open('a') as a:
    for i in a:
        line = i.rstrip('\n')
        while True:
            user = _input("enter line: ")
            if user == "LINE!":
                print('%s\n' % line)
                break
            if line == user:
                break
            print("No! Try again...")
    print("Good!")

Upvotes: 2

James K
James K

Reputation: 3752

The short answer is: to stop a loop, use the break statement eg

while True:
   q = input("What is your quest? ")
   if q == "To seek the holy grail":
       break
   print("That's not right, try again")
#Program continues.

In your case I would consider thinking about the logic of the loops. You seem to have nested loops unnecessarily. A single for loop through the file should be enough.

Upvotes: 0

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