Eroare de compilare: user.cpp: In function ‘long long int abs(int)’: user.cpp:20:20: error: new declaration ‘long long int abs(int)’ long long abs(int x) ^ In file included from /usr/include/c++/4.8/cstdlib:72:0, from /usr/include/c++/4.8/ext/string_conversions.h:41, from /usr/include/c++/4.8/bits/basic_string.h:2815, from /usr/include/c++/4.8/string:52, from /usr/include/c++/4.8/bits/locale_classes.h:40, from /usr/include/c++/4.8/bits/ios_base.h:41, from /usr/include/c++/4.8/ios:42, from /usr/include/c++/4.8/istream:38, from /usr/include/c++/4.8/fstream:38, from user.cpp:1: /usr/include/stdlib.h:771:12: error: ambiguates old declaration ‘int abs(int)’ extern int abs (int __x) __THROW __attribute__ ((__const__)) __wur; ^