AboutPrince M. Premnath Expertise Years of research in C/C++ Will bring you all facts regarding , OOPS , SVGA , MOUSE , BIOS , IVT , Feel free to query me :-)
Question QUESTION: hello sir!
i have problem with signed and unsigned char.
if i declare unsigned char ch=-123; its output is same as if i use signed instead of unsigned. then what is use unsigned .then why we take unsigned take values from 0 to 255.
ANSWER: Hai dear Deepak !
Certainly there is a difference upon using unsigned and signed data types !
take a look at this small programme
#include<iostream.h>
void main()
{
unsigned char a = - 123;
signed char b = -123;
cout<<(int)a;
cout<<(int)b;
}
O/P Of this program is 133 -123 , note that the results were not same , in a signed char the last bit (MSB) will be used for storing the sign and hence it just allows -128 to 127 for signed integer , in case of unsigned integer , all the bits are used to store the values and hence you are free to store from 0 to 255 !
Thanks and Regards !
Prince M. Premnath
---------- FOLLOW-UP ----------
QUESTION: then how output will be 133 of a. -123 of b is understandable . but if -123 is stored as 01111011.how it represent 133.
Answer Hai dear Deepak !
While assigning a -ve number to an unsigned char type , it will take few modification in internal representation ,say the MSB will be set to 0 and all other bit were set to 1 if the value assigned to unsigned char is -1 and so on for all other values within the accepted range !
