Submitted by tushar pramanick on Thu, 03/07/2013 - 12:56

Question and Answer

    Q Which bit can be used as the sign bit in an integer?

    A The leftmost bit can be used as the sign bit for an integer. For instance, assume the int data type is 16 bits long. If you count the bit position from right to left, and the first bit counted is bit 0, then bit 15 is the leftmost bit that can be used as the sign bit.

    Q What can the %lu format specifier do?

    A The %lu format specifier can be used to convert the corresponding datum to the unsigned long int data type. In addition, the %lu format specifier is equivalent to %Lu.

    Q When do I use short and long?

    A If you need to save memory space, and you know the value of an integer data variable stays within a smaller range, you can try to use the short modifier to tell the C compiler to reduce the default memory space assigned to the variable, for instance, from 32 bits to 16 bits.

    On the other hand, if a variable has to hold a number that is beyond the current range of a data type, you can use the long modifier to increase the storage space of the variable in order to hold the number.

    Q Does the sin() function take a value in degrees or in radians?

    A Like other trigonometric math functions in C, the sin() function takes a value in radians. If you have an angle in degrees, you have to convert it into the form of radians. The formula is:

    radians = degree * (3.141593 / 180.0).

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    Q Why is random access to a disk file necessary?