Thread: Numeric Ranges

It still is truncated, but remember that a signed integer is represented by two's complement. So for example "0x7FFF" is 32767 for both unsigned and signed short, but "0x8000" is 32768 for unsigned and -32768 for signed.

And no, a typical int( one that is 32 bits ) can represent anything from 0 to 4294967295.

It basically behaves like this (using a 3 bit number here):

Code:

binary  unsigned  signed

   000         0       0
   001         1       1
   010         2       2
   011         3       3
   100         4      -4
   101         5      -3
   110         6      -2
   111         7      -1

Demo:

Code:

void print(unsigned short us) {
    cout << "unsigned(" << us << ") -> signed(" << static_cast<signed short>(us) << ")\n";
}

int main()
{
    unsigned short us;

    // Lower values identical
    for (us = 0; us < 8; ++us) {
        print(us);
    }

    cout << '\n';

    // Mid values, signed type becomes negative (starting with maximum negative value)
    for (us = 32764; us < 32772; ++us) {
        print(us);
    }

    cout << '\n';

    // Highest values, signed type has counted down to -1
    for (us = 65528; us < 65535; ++us) {
        print(us + 1);
    }

    cout << '\n';
}