No Links Solution - Intro to Computer Science Udacity Italian English

No Links Solution - Intro to Computer ScienceYouTube↗ IA↗(long shot)
Education 2.6K views 21 likes 3 dislikes 02 Mar 2012

Udacity 651K subscribers United States YouTube↗

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Questa è la soluzione.

So here's the solution

Aggiungiamo una istruzione "if" perchè vogliamo prendere una decisione

So we want to add an "if" statement because we want to make a decision

Vogliamo testare

se start_link è uguale a -1

If the start_link is equal to -1

Significa che non abbiamo trovato quello che stavamo cercando

So that means that we did not find what we were looking for

e find ritorna -1, così il valore di start_link è -1.

find returns to -1, so the value of start link is -1

Poi non vogliamo fare il resto, perchè non abbiamo una url

Well, then we don't want to do the rest, we don't have an URL to look for

Vogliamo in questo caso ritornare i valori speciali "None" e "0"

What we want to do is return the special value "None" and zero

Così questa è la modifica

So that's the change

Ora quando eseguiamo con questa stringa che non ha link

Now when we run this with this string that does not have a link

in output abbiamo url uguale "None"

what we get as the output for the url is "None"

Non possiamo dire che non sia una stringa dal modo in cui viene stampato, ma è diverso da una stringa

We can't tell that's not a string, the way it prints out, but it's different from a string

"None" è una sorta di "False"

and one thing that we can do with "None" is sort of like "False"

Così se il valore di una espressione di test in una "if" è "None"

So if the value of the test expression in an "if" is "None"

è trattata nello stesso modo di "False"

that's treated the same way as "False"

Così se l'url ritornata qui è "None", allara stamperemo "Not here" [Non qui]

So if url returned here is "None", then we'll print "Not here!"

Penso significhi che siamo "here" [qui], ma non siamo "here" [qui].

I guess that means we are here, but we are not "Here!"

Vediamo che otteniamo "Not here"

So here's what we get, we see that we got "Not here!"

quando passiamo una stringa che non contiene un tag di link

when we passed in a string that did not contain a link tag

se torniamo ad una stringa che contiene link

if we go back to the string that has a link tag

ed eseguiamo il codice, vedremo che l'url è una stringa che viene trattata come "True"

and now we run the code, we'll see that the url was some string that's treated as "True"

e viene stampato "Here".

and we get the print "Here!"

Così la condizione di test non è necessario sia solo "True" o "False"

So the test condition for a boolean doesn't necessarily have to be just "True" or "False"

ma Python interpreta diversi valori come "True" e "False"

Python will interpret different values as "True" and "False"

e la cosa importante qui è che qualsiasi valore si tringa diverso dalla stringa vuota viene interpretato come "True"

and the important thing here is that any string value other than empty string is treated as "True"

e andiamo da questa parte della "if".

and we'll go through this part of the "if"

Il valore "None" è trattato come "False" e andremo alla "else"

The value "None" is treated as "False" and we will go to the else

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