Regarding input

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Regarding input

Post by rafagiu »

Hello, everyone.

What's the best way to read an input file where the test cases are separeted by line breaks or blank lines, instead of having an explicit counter?


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this is test case one
this is test case two
Instead of

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5 this is test case one
5 this is test case two
The second case has an explicits the number of test cases (2) and each test case explicits the number of input elements (5 and 5).

For the first case, I have been reading the input with fgets into a string and processing its elements with sscanf, but it's quite boring and very little elegant this way. Can anybody share a better alternative?

Thanks in advance![/code]

Martin Macko
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Location: European Union (Slovak Republic)

Re: Regarding input

Post by Martin Macko »

Try to use %[...] scanf conversions. For instance, to parse the input

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aaaa      bbbbb cc
eeeee    ffff   
you can write something like
code wrote:#include <stdio.h>

int main(void)
{ l=0;
........char s[1000];

........while (!feof(stdin))
................printf("line %d:", ++l);
................while (scanf("%[^ \n]%*[ ]", s)>0) printf(" '%s'", s);
................scanf("%*c%*[ ]");

........return 0;
The output of the program to the given input is

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line 1: 'aaaa' 'bbbbb' 'cc'
line 2:
line 3: 'ddddd'
line 4: 'eeeee' 'ffff'
For more information on %[...] try man scanf.
Last edited by Martin Macko on Mon Jun 12, 2006 3:30 am, edited 1 time in total.

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Post by chunyi81 »

Use gets or fgets function. If length of line read in is > 0, then parse using strtok function.

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