Eroare de compilare: user.cpp: In function ‘int main()’: user.cpp:32:78: error: call of overloaded ‘abs(double)’ is ambiguous aria += abs(x1 * y2 + x2 * y3 + x3 * y1 - x3 * y2 - x2 * y1 - x1 * y3); ^ In file included from /usr/include/c++/6/cstdlib:75:0, from /usr/include/c++/6/ext/string_conversions.h:41, from /usr/include/c++/6/bits/basic_string.h:5417, from /usr/include/c++/6/string:52, from /usr/include/c++/6/bits/locale_classes.h:40, from /usr/include/c++/6/bits/ios_base.h:41, from /usr/include/c++/6/ios:42, from /usr/include/c++/6/ostream:38, from /usr/include/c++/6/iostream:39, from user.cpp:1: /usr/include/stdlib.h:774:12: note: candidate: int abs(int) extern int abs (int __x) __THROW __attribute__ ((__const__)) __wur; ^~~ In file included from /usr/include/c++/6/ext/string_conversions.h:41:0, from /usr/include/c++/6/bits/basic_string.h:5417, from /usr/include/c++/6/string:52, from /usr/include/c++/6/bits/locale_classes.h:40, from /usr/include/c++/6/bits/ios_base.h:41, from /usr/include/c++/6/ios:42, from /usr/include/c++/6/ostream:38, from /usr/include/c++/6/iostream:39, from user.cpp:1: /usr/include/c++/6/cstdlib:180:3: note: candidate: long long int std::abs(long long int) abs(long long __x) { return __builtin_llabs (__x); } ^~~ /usr/include/c++/6/cstdlib:172:3: note: candidate: long int std::abs(long int) abs(long __i) { return __builtin_labs(__i); } ^~~ user.cpp:12:35: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("aria.in", "r", stdin); ^ user.cpp:13:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("aria.out", "w", stdout); ^ user.cpp:16:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &n); ^ user.cpp:18:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf", &x1); ^ user.cpp:19:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf", &y1); ^ user.cpp:21:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf", &x2); ^