There is no theoretical limit. The BigInteger class allocates as much memory as it needs for all the bits of data it is asked to hold. There are, however, some practical limits, dictated by the memory available. And there are further technical limits, although you’re very unlikely to be affected: some methods assume that the … Read more
As Miles hinted: The C++ code text is bound by the rules of the C++ language (integer overflow = bad), but the compiler is only bound by the rules of the cpu (overflow=ok). It is allowed to make optimizations that the code isn’t allowed to. But don’t take this as an excuse to get lazy. … Read more
Known bug. Related to http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6196102 http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=6357214 and others. I think they’re considered low-priority to fix because they don’t come up in the real world.
According to the standard So, from your quote: argv[argc] is required to be a null pointer Therefore, argc cannot overflow, because then the above statement would not be true. In practice In practice, the total size of the arguments passed to a program is limited. On my Linux/x64 system: $ getconf ARG_MAX 2097152 Therefore, the … Read more
2147483647 + 1 is evaluated as the sum of two ints and therefore overflows. 2147483648 is too big to fit in an int and is therefore assumed by the compiler to be a long (or a long long in MSVC). It therefore does not overflow. To perform the summation as a long long use the … Read more
Jim Martin’s comment from §3.6.9. “Using AUTO_INCREMENT” of the MySQL documentation: Just in case there’s any question, the AUTO_INCREMENT field /DOES NOT WRAP/. Once you hit the limit for the field size, INSERTs generate an error. (As per Jeremy Cole) A quick test with MySQL 5.1.45 results in an error of: ERROR 1467 (HY000): Failed … Read more
C# integer operations don’t throw exceptions upon overflow by default. You can achieve that via the project settings, or by making the calculation checked: int result = checked(largeInt + otherLargeInt); Now the operation will throw. The opposite is unchecked, which makes any operation explicitly unchecked. Obviously, this only makes sense when you’ve got checked operations … Read more
Yes, but… It is certainly possible, but it is usually nonsensical (for any program that doesn’t use billions of these numbers): #include <stdint.h> // don’t want to rely on something like long long struct bad_idea { uint64_t var : 40; }; Here, var will indeed have a width of 40 bits at the expense of … Read more
Integer variables are stored as 16-bit (2-byte) numbers Office VBA Reference Long (long integer) variables are stored as signed 32-bit (4-byte) numbers Office VBA Reference So, the benefit is in reduced memory space. An Integer takes up half the memory that a Long does. Now, we are talking about 2 bytes, so it’s not going … Read more
I’m going to assume that the online compilers use GCC or compatible compiler. Of course, any other compiler is also allowed to do the same optimization, but GCC documentation explains well what it does: -faggressive-loop-optimizations This option tells the loop optimizer to use language constraints to derive bounds for the number of iterations of a … Read more