Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:31:27: error: call of overloaded ‘abs(long long int)’ is ambiguous A = abs (a * d - b * c); ^ In file included from /usr/include/c++/5/cstdlib:72:0, from /usr/include/c++/5/ext/string_conversions.h:41, from /usr/include/c++/5/bits/basic_string.h:5249, from /usr/include/c++/5/string:52, from /usr/include/c++/5/bits/locale_classes.h:40, from /usr/include/c++/5/bits/ios_base.h:41, from /usr/include/c++/5/ios:42, from /usr/include/c++/5/istream:38, from /usr/include/c++/5/fstream:38, from user.cpp:1: /usr/include/stdlib.h:774:12: note: candidate: int abs(int) extern int abs (int __x) __THROW __attribute__ ((__const__)) __wur; ^ user.cpp:10:11: note: candidate: long long int abs(long long int) long long abs (long long a) { ^ In file included from /usr/include/c++/5/ext/string_conversions.h:41:0, from /usr/include/c++/5/bits/basic_string.h:5249, from /usr/include/c++/5/string:52, from /usr/include/c++/5/bits/locale_classes.h:40, from /usr/include/c++/5/bits/ios_base.h:41, from /usr/include/c++/5/ios:42, from /usr/include/c++/5/istream:38, from /usr/include/c++/5/fstream:38, from user.cpp:1: /usr/include/c++/5/cstdlib:174:3: note: candidate: long long int std::abs(long long int) abs(long long __x) { return __builtin_llabs (__x); } ^ /usr/include/c++/5/cstdlib:166:3: note: candidate: long int std::abs(long int) abs(long __i) { return __builtin_labs(__i); } ^