how do I convert a long long int into a char array?

Without lossing information?

Quote:

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Originally Posted by Once-ler

Without lossing information?

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To convert a long long int into a char array, use the sprintf function with the long long int specifier

How do I get this to work?

Code:

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  #include <stdio.h>
  int main()
  {
      char b[1000];
      long long int i = 42393848474;
      sprintf( b, "Formatted data:  %d", i );
      puts( b );
  }

---

returns a value of -555824486
and larger numbers like long long int i = 88842393848474; shows 995330714
I have no idea what is happening here.
if I increase char b[] much more the compiler gives me the too big error
I need it to do the full spectrum of 18446744073709551615
Thanks

%d format is for int. Not for long long int. Use the wrong format specifier, and the result is undefined behaviour.

Look at Printf format strings - Cprogramming.com

Bye, Andreas

Thanks you guys.
add ll in %lld fixed the problem. Thankyou so much.

except that it dosen't work all the way to 18446744073709551615
I keep getting a negative number

Quote:

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Originally Posted by Once-ler

except that it dosen't work all the way to 18446744073709551615
I keep getting a negative number

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Because long long range (64-bit) is from -9223372036854775808 to 9223372036854775807

what if I want to work with all positive numbers what would the range be then?

You can use "unsigned long long" in that case.

I tried that with 18446744073709551615 and it keeps giving me a negative number
Thanks for your help.

sprintf should also be changed to "%ulld" ( sorry, I forgot about that :D )

Code:

---

#include <stdio.h>
  int main()
  {
    char b[1000];
    unsigned long long int i =18446744073709551615 ;
      sprintf( b, "Formatted data:  %ulld", i );
      puts( b );
      if (i&1) printf("is odd");
  }

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doing that gives me back a number that is 4294967295lld

They mean %llu. Check "man 3 sprintf".

Thank you.

Some implementations seem to have trouble with %llu and formatting perhaps other "large" types -- e.g. Microsoft Windows using the standard CRT. For this reason also consider using the <inttypes.h> header if it is possible. The following should work in any compliant compiler including in MS-Windows

Code:

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#include <stdio.h>
#include <inttypes.h>

int main(void)
{
    uint64_t i = 18446744073709551615ul;
    printf("Formatted data:  %" PRIu64 "\n", i );
    if (i&1) printf("is odd");
    return 0;
}

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