Is there is a difference between size_t and container::size_type?
What I understand is size_t is more generic and can be used for any size_types.
But is container::size_type optimized for specific kinds of containers?
C++ – ‘size_t’ vs ‘container::size_type’
ccontainer-data-typesize-type
Related Solutions
gcc and g++ are compiler-drivers of the GNU Compiler Collection (which was once upon a time just the GNU C Compiler).
Even though they automatically determine which backends (cc1 cc1plus ...) to call depending on the file-type, unless overridden with -x language, they have some differences.
The probably most important difference in their defaults is which libraries they link against automatically.
According to GCC's online documentation link options and how g++ is invoked, g++ is equivalent to gcc -xc++ -lstdc++ -shared-libgcc (the 1st is a compiler option, the 2nd two are linker options). This can be checked by running both with the -v option (it displays the backend toolchain commands being run).
This cheat sheet provides a pretty good summary of the different containers.
See the flowchart at the bottom as a guide on which to use in different usage scenarios:
Created by David Moore and licensed CC BY-SA 3.0
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Best Answer
The standard containers define
size_typeas a typedef toAllocator::size_type(Allocator is a template parameter), which forstd::allocator<T>::size_typeis typically defined to besize_t(or a compatible type). So for the standard case, they are the same.However, if you use a custom allocator a different underlying type could be used. So
container::size_typeis preferable for maximum generality.