Standard library header <ccomplex> (C++11)(until C++20), <complex.h> (C++11)
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                    This header was originally in the C standard library as <complex.h>.
 Includes | |
|   (C++11)  | 
Complex number type | 
Notes
<ccomplex> is deprecated in C++17 and removed in C++20. Corresponding <complex.h> is still available in C++20.