Compilare: user.cpp: In function ‘long long int calc(int)’: user.cpp:13:30: warning: unused variable ‘s’ [-Wunused-variable] long long sprod=0,nrprod,s; ^ user.cpp: In function ‘int main()’: user.cpp:51:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] { freopen("tarabe.in", "r",stdin); ^ user.cpp:52:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("tarabe.out", "w",stdout); ^ user.cpp:55:26: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &k); ^ user.cpp:57:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &v[i].b, &v[i].a); ^