Thread: long long array problem

I perfer that the result is "0xFFFFFFFFFFFCCFCC"
but in face, the result is "0xFFFCCFCC"?
any bugs in my program?

Code:

#include <stdio.h>
int    main(void)
{
    int f;
    long long tempdata;
    long long* ptable;




     long long table [16]=
      {
      0xFFFFFFFFFFFCCFCC, //2>
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,
      0xCCCCCCCCCCCCCCCC,    //1
      };






    f=0;
    ptable = table;
    tempdata = *(ptable+(f*256)+(0*16)+0);
    printf("result= %x",tempdata);
    return 0;


}

The printf specifier "%x" is used to print an int in hex. Since you're using long long at all I assume "int" is smaller than "long long" on your platform, probably 32 bits.

Using "%llx" should work with most compilers, including GCC. MSVC uses something different, from memory it is "%I64x"

1) you need to use printf("result = %llx", tempdata); for 64 bit values

2) if f is ever anything but 0 you are going to cause an integer overflow, which will most likely not be caught because of the lack of runtime checking in C.

Originally Posted by smokeyangel

The printf specifier "%x" is used to print an int in hex. Since you're using long long at all I assume "int" is smaller than "long long" on your platform, probably 32 bits.

Using "%llx" should work with most compilers, including GCC. MSVC uses something different, from memory it is "%I64x"

worked! thankyou