+ 3

Can anyone help me? I don't understand loops

https://code.sololearn.com/cDR5svhfof00/?ref=app https://www.sololearn.com/learn/JUMP_LINK__&&__Python__&&__JUMP_LINK/2435/?ref=app I try a lot but i am still confused. I don't understand this lesson. (I will appreciate if anyone can explain this to me as simple as he/she can.)

25th Nov 2019, 4:57 PM
Elen V
Elen V - avatar
15 Antworten
+ 8
words = ["hello", "world", "spam", "eggs"] counter = 0 max_index = len(words) - 1 The first element in words starts at index 0: words [0] = "hello"; ... words [3] = "eggs" The length of words is 4, because it contains 4 elements. Now it should be clear why max_index = len (words) - 1 = 4 - 1 = 3 while counter <= max_index: This is your condition. The loop runs until counter <= max_index. If the counter gets larger the loop stops. word = words[counter] print(word + "!") counter = counter + 1 counter = 0 -> word = words [0] = "hello" print hello! increment counter counter = 1 -> word = words [1] = "world" print world! increment counter and so on... counter gets 4 -> larger than max_index -> stop loop As you can see the loop prints all elements of your list.
25th Nov 2019, 5:21 PM
Denise Roßberg
Denise Roßberg - avatar
+ 3
Denise Roßberg really thank you!
25th Nov 2019, 5:25 PM
Elen V
Elen V - avatar
+ 3
Elen V Your welcome :)
25th Nov 2019, 5:27 PM
Denise Roßberg
Denise Roßberg - avatar
+ 3
Loops : In your code: words = ["hello", "world", "spam", "eggs"] counter = 0 max_index = len(words) - 1 while counter <= max_index: word = words[counter] print(word + "!") counter = counter + 1 You are saying to the program while counter(is 0) is less than or equal to max index(length of the array words note : the tru e length of the array is 4 but in this example is 3 simply because the array start counting from 0 ) Print word +! Where word is the array words with the number counter inside it. Counter = counter + 1 Means in every value of counter returns it value and add 1 to it ex If counter = 2 The loop will start counting from 2 to the end Of the loop The end of loop ex While number<=number2 Number:beginning of the loop Number2:the end of the loop You can reverse the loop While number>=number2 Bla Bla Number = number -1 Hope this explanation will help you 😊 Peace
25th Nov 2019, 6:04 PM
$p@rK
$p@rK - avatar
+ 3
Moumen Al_Bakkar 😂😂 sorry Thank you too
25th Nov 2019, 6:14 PM
Elen V
Elen V - avatar
+ 3
Loops are used to repeat code segments.
26th Nov 2019, 8:27 AM
Sonic
Sonic - avatar
+ 3
Hope you understand now.
27th Nov 2019, 2:41 AM
Sonic
Sonic - avatar
+ 2
$p@rK thanks 👍
25th Nov 2019, 6:09 PM
Elen V
Elen V - avatar
+ 2
You are welcome 😊
25th Nov 2019, 6:10 PM
$p@rK
$p@rK - avatar
+ 2
No need to thank me.
26th Nov 2019, 8:28 AM
Sonic
Sonic - avatar
+ 2
Sonic 👍
26th Nov 2019, 11:33 AM
Elen V
Elen V - avatar
+ 1
if you want to write your name one time u can write (in C#) { Console.WriteLine("Elen"); } if you want to write it twise you can copy and paste last line... But how about 100 times ? or 1000 ? do u want to copy paste copy past...... OF COURSE no.. so we have to use loop sometimes to repeat things without wasting time.
25th Nov 2019, 5:26 PM
Moumen Al_Bakkar
Moumen Al_Bakkar - avatar
+ 1
Elen V why didn't u thank me 😐
25th Nov 2019, 6:09 PM
Moumen Al_Bakkar
Moumen Al_Bakkar - avatar
+ 1
Sonic, yes now i understand and i want to thank you all of you 🤗
27th Nov 2019, 5:09 AM
Elen V
Elen V - avatar
+ 1
I can try it to explain in pseudocode. You got a kind of data. Lets say a list. ex_list = [1,2,3,4] And you want to do something with every elenent of the data, then you say: for [each] element in . The tool is for i in ex_list: do something. Hope it helps.
27th Nov 2019, 2:29 PM
Sven_m
Sven_m - avatar