unsigned

I am so confused about size_t . I have searched on the internet and everywhere mentioned that size_t is an unsigned type so, it can represent only non-negative values. My first question is: if it is used to represent only non-negative values, why don't we use unsigned int instead of size_t ? My second question is: are size_t and unsigned int interchangeable or not? If not, then why? And can anyone give me a good example of size_t and briefly its workings? if it is use to represent non negative value so why we not using unsigned int instead of size_t Because unsigned int is not the only

Possible Duplicate: signed to unsigned conversion in C - is it always safe? Let's say I declare a variable of type unsigned int : unsigned int x = -1; Now -1 in two's complement (assuming 32 bit machine) is 0xFFFFFFFF. Now when I assigned this value to x, did the value 0x7FFFFFFF get assigned to x? If it were so, then printf ("%d",x); would have printed the decimal equivalent of 0x7FFFFFFF, right? But, clearly this isn't happening, as the value that gets printed is -1. What am I missing here? Edit: I know that we can use the %u format specifier to print unsigned values. But that doesn't help

Let's say I have this number i = -6884376 . How do I refer to it as to an unsigned variable? Something like (unsigned long)i in C. Assuming : You have 2's-complement representations in mind; and, By (unsigned long) you mean unsigned 32-bit integer, then you just need to add 2**32 (or 1 << 32) to the negative value. For example, apply this to -1: >>> -1 -1 >>> _ + 2**32 4294967295L >>> bin(_) '0b11111111111111111111111111111111' Assumption #1 means you want -1 to be viewed as a solid string of 1 bits, and assumption #2 means you want 32 of them. Nobody but you can say what your hidden

Consider the following code: template<bool> class StaticAssert; template<> class StaticAssert<true> {}; StaticAssert< (-1 < sizeof(int)) > xyz1; // Compile error StaticAssert< (-1 > sizeof(int)) > xyz2; // OK Why is -1 > sizeof(int) true? Is it true that -1 is promoted to unsigned(-1) and then unsigned(-1) > sizeof(int) . Is it true that -1 > sizeof(int) is equivalent to -1 > size_t(4) if sizeof(int) is 4. If this is so why -1 > size_t(4) is false? Is this C++ standard comformant? The following is how standard (ISO 14882) explains abort -1 > sizeof(int) Relational operator `>' is defined in 5