- Need help on c++Linked list - 1 Update
- Facing problem reading file character-by-character using get() - 4 Updates
| Paul N <gw7rib@aol.com>: Sep 24 02:26PM -0700 On Friday, September 22, 2017 at 2:12:13 AM UTC+1, Mwater07 wrote: > for(int i=0; i<n;i++) > head=new node (a[i],head); > } I think you have problems here. Firstly, what does "link" mean? Are you simply trying to set head to 0? Also, you don't seem to be supplying enough arguments to the "new node", you want to pass the index i, the value a[i] and head. While that may get it working - you also said you were only going to store the non-zero values, so you need an "if"; you're throwing away any previous nodes in the list, which might be a bad move and it would certainly be usual to free them; the function doesn't "create" a list as such, it fills it up with the values from a vector so the name is a bit misleading; and you might want to use NULL instead of 0 for consistency with your other code. Hope that helps. Paul. [Snip rest] |
| bintom <binoythomas1108@gmail.com>: Sep 24 07:19AM -0700 Hi! I have the following short program to read a text file character-by-character using get(). int main() { char ch; ifstream in("Text.txt"); while(in) { in.get(ch); cout.put(ch); } in.close(); } In the output, I am getting the very last character in the text file appearing twice. I have no clue why ... Thanks for any help |
| bintom <binoythomas1108@gmail.com>: Sep 24 07:23AM -0700 I have the following code, which is printing the last character in the text file two times. int main() { char ch; ifstream in("Test.txt"); while(in) { in.get(ch); cout.put(ch); } in.close(); getch(); } Any help will be hugely appreciated. |
| "Alf P. Steinbach" <alf.p.steinbach+usenet@gmail.com>: Sep 24 05:03PM +0200 On 9/24/2017 4:19 PM, bintom wrote: > in.close(); } > In the output, I am getting the very last character in the text file > appearing twice. I have no clue why ... Because you don't check the result of the `get` call. Change the loop to while( in.get( ch ) ) { cout.put( ch ); } That's idiomatic and, because `get` returns a reference to the stream which converts to `bool` via a call to `fail()` + negation, it's the short version of for( ;; ) { char ch; in.get( ch ); if( in.fail() ) { break; } cout.put( ch ); } But you don't want to write that. Cheers & hth., - Alf |
| Barry Schwarz <schwarzb@dqel.com>: Sep 24 11:08AM -0700 On Sun, 24 Sep 2017 07:19:54 -0700 (PDT), bintom > in.close(); >} >In the output, I am getting the very last character in the text file appearing twice. I have no clue why ... Alf has already given you the technical answer. Your confusion arises because you made a false assumption about the state of in. Here is one way to analyze the situation should you run into something similar in the future. It falls under the general heading of "pretend you are the computer". Consider the sequence if the file contains two characters, '8' and '9'. You open the file. The ifstream object in now corresponds to that file. The while expression evaluates to true. You read the character '8'. The operation completes normally. You write the contents of ch ('8'). The while expression evaluates to true. You read the character '9'. The operation completes normally. You write the contents of ch ('9'). The while expression evaluates to true. You attempt to read another character. There is none available. The operation fails. Object ch is unchanged. You write the contents of ch ('9'). Now the while expression evaluates to false and you close the file. Reading the last character of a file and no further does not set "end of file" status. That only happens when you attempt to read beyond the last character. -- Remove del for email |
| You received this digest because you're subscribed to updates for this group. You can change your settings on the group membership page. To unsubscribe from this group and stop receiving emails from it send an email to comp.lang.c+++unsubscribe@googlegroups.com. |
No comments:
Post a Comment