C is a strongly typed, weakly checked language.
– D. M. Ritchie
The standard library for the C language is with very minor modifications incorporated into the C++ standard library. The C standard library provides quite a few functions that have proven useful over the years in a wide variety of contexts – especially for relatively low-level programming.
There are more C standard-library functions than are presented here; see a good C textbook, such as “Kernighan and Ritchie” [Kernighan,1988] or the ISO C standard [C,2011], if you need to know more.
The <cstdio> I/O system is based ...