Little endian to big endian

//2-byte number
int SHORT_little_endian_to_big_endian( int i)
{
    return (( i>>8)&0xff)+((i<<8)&0xff00);
}
//4-byte number
int INT_little_endian_To_big_endian(int i)
{
    return((i&0xff)<<24)+((i&0xff00)<<8)+((i&0xff0000)>>8)+((i>>24)&0xff);
}

Give Me a String at Random from THIS File

Constraint:
1) You can make only one sequential pass through the file.
2) You may not store any additional information like a table of offsets.

I would like to receive the answers from you all. After receiving answers from you i will post the answer.

PS: Seems this question also asked in Microsoft Inverview.

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Solution: ( Taken from a book, if anyone know best solution, please post comment )

The basic technique is to pick survivors, and recalculate as you go along. This is so com-putationally inefficient that it's easy to overlook. You open the file and save the first string. At this point you have one candidate string with a 100% probability of picking it. While remembering the first string, you read the next string. You now have two candidates, each with a 50% probability. Pick one of them,save it, and discard the other. Read the next string, and choose between that and the saved string,weighting your choice 33% toward the new string and 67% toward the survivor (which represents the winner of the previous two-way selection). Save the new survivor.

Keep on doing this throughout the entire file, at each step reading string N, and choosing between that(with probability 1/N) and the previous survivor, with probability (N - 1)/N. When you reach the endof the file, the current survivor is the string picked at random!

sizeof() Vs strlen()

In C language Difference between sizeof() and strlen()

Consider the following example:

/* Example for sizeof( ) , strlen( ) */
#include 
main()
{
       char String[]="Hello";

       printf("\n SIZE OF String %d STRING LENGTH %d", 
       sizeof( String ), strlen( String ) );
}

Result:
SIZE OF String 6 STRING LENGTH 5.

Every String contains a NULL character( '\0' ) at the end. The sizeof() function will include that NULL character also for calculating string size but strlen() function not.

Why is sizeof('a') not 1?
Perhaps surprisingly, character constants in C are of type int, so sizeof('a') is sizeof(int) (though it's different in C++).

Result:
In Turbo C output is: 2
In Turbo C++ output is: 1

Is It possible to call a Static function by a Function Pointer?

Yes It is Possible. Eventhough, static functions are local to that file, if we assign that function address to a same type (prototype should be strictly same, otherwise result unknown) function pointer. We can call that function indirectly...