Binary presentation of negative integer in Java

Question

Please, help me to understand binary presentation of negative integers.

For example we have 5. Binary presentation of 5 is 00000000.00000000.00000000.00000101

Answer 1

Here is an example for 2's compliment:

If you have -30, and want to represent it in 2's complement, you take the binary representation of 30:

0000 0000 0000 0000 0000 0000 0001 1110

Invert the digits.

1111 1111 1111 1111 1111 1111 1110 0001

And add one.

1111 1111 1111 1111 1111 1111 1110 0010

Converted back into hex, this is 0xFFFFFFE2. And indeed, suppose you have this code:

#include 

int main() {
    int myInt;
    myInt = 0xFFFFFFE2;
    printf("%d\n",myInt);

    return 0;
}

That should yield an output of -30. Try it out if you like.