dush1729's blog

How to process blank line in c++?
By dush1729, history, 11 years ago, In English

I am trying to solve Niceness of the string but i am getting WA because i think i am unable to process blank lines. For blank lines output will be zero. I am using scanf(" %[^\n]s",a) which will ignore blank lines.

My code

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11 years ago, hide # |
 
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std::getline()

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    11 years ago, hide # ^ |
     
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    Thank you! getline will behave weirdly if we don't ignore \n. So i came across this. Putting cin.ignore() after scanf("%d",&T) and using getline() gave AC.

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      11 years ago, hide # ^ |
       
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      There is no weirdness in getline:

      size_t n;
cin >> n;
string s;
getline(cin, s); // read pointer is just before the end of line, so the empty line is returned after number reading
for (size_t i = 0; i < n; i++)
{
    getline(cin, s); // works, as expected
}
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        11 years ago, hide # ^ |
         
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        Got it. By adding extra getline before taking string as input we can ignore \n.

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11 years ago, hide # |
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Replacing scanf("%s",a) with gets(a) may help. But remember to getchar() after scanf("%d",&T) to skip the '\n' in the first line.

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    11 years ago, hide # ^ |
     
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    Looks like getchar works a bit faster than cin.ignore(). Thanks!

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    11 years ago, hide # ^ |
     
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    If you want to skip '\n', you can write: scanf("%d\n",&T). But this works with bugs when you debug your program (if you are not reading from the file).

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scanf is for queers

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