Eroare de compilare: user.cpp:8:18: error: ‘double y1’ redeclared as different kind of symbol double x, y, x1, y1, newX, newY, S; ^ In file included from /usr/include/features.h:357:0, from /usr/include/i386-linux-gnu/c++/4.8/bits/os_defines.h:39, from /usr/include/i386-linux-gnu/c++/4.8/bits/c++config.h:420, from /usr/include/c++/4.8/iostream:38, from user.cpp:1: /usr/include/i386-linux-gnu/bits/mathcalls.h:243:1: error: previous declaration of ‘double y1(double)’ __MATHCALL (y1,, (_Mdouble_)); ^ user.cpp: In function ‘int main()’: user.cpp:17:7: error: assignment of function ‘double y1(double)’ y1 = y; ^ user.cpp:17:7: error: cannot convert ‘double’ to ‘double(double)throw ()’ in assignment user.cpp:24:19: error: invalid operands of types ‘double’ and ‘double(double)throw ()’ to binary ‘operator*’ S = S + newX * y1 - x1 * newY; ^ user.cpp:12:34: 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:13:36: 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:14:21: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d\n", &n); ^ user.cpp:15:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf %lf\n", &x, &y); ^ user.cpp:19:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%lf %lf\n", &newX, &newY); ^