Compilare: user.cpp: In function ‘int main()’: user.cpp:40:13: warning: variable ‘nr1’ set but not used [-Wunused-but-set-variable] int nr1 = 0, nr2 = 0; ^ user.cpp:40:22: warning: variable ‘nr2’ set but not used [-Wunused-but-set-variable] int nr1 = 0, nr2 = 0; ^ user.cpp:32:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("twosets.in", "r", fin); ^ user.cpp:33:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("twosets.out", "w", fout); ^ user.cpp:36:16: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] R("%d", &t); ^