[Tutor] FW: find() problem

[Evert Rol]

> > > def find(strng, ch, start, step=1):
> > >     index = start
> > The problem lies here, if you do a print on index, it never gets past
> > the first index of the number, so
> > your while loop below goes into an infinite loop.
> > 
> > For example:
> > find('starfruit','t',0) <- First time will return 1
> > find('starfruit','t',1) <- Still returns 1. Infinite loop
> > 
> > >     while 0 <= index < len(strng):
> > >         if strng[index] == ch:
> > >             return index
> > >         index += step
> > >     return -1
> > >
> > > fruit=""
> > > letter=""
> > > fruit= raw_input("Enter a sort of fruit: ")
> > > letter = raw_input("Enter the character which must be counted: ")
> > > start=0
> > > aantal=0
> > > while 0 <=start < len(fruit):
> > >     x=find (fruit,letter, start)
> > >     aantal +=1
> > >     start=x
> > > print "De letter", letter , "komt", aantal , "maal voor in het woord", fruit
> > >
> > 
> > HTH,
> > Tino
> 
> Hello, 
>  
> Your right. index get never past 1 
> But in my opinion when something is found then x will be the place where the character is be found.
> After that the counter is increased and start gets the value of x.
> So start should change.
>  
> Now finding out why this is not happening.

You're including the previous found index; so it will just find the character at that same index again. You need to start the next search one index further down the word.


>  
> But thanks for the help.
>  
> Roelof
>  
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