Compilare: user.cpp: In function ‘int main()’: user.cpp:30:9: warning: unused variable ‘T’ [-Wunused-variable] int T, k; ^ user.cpp:30:12: warning: unused variable ‘k’ [-Wunused-variable] int T, k; ^ user.cpp:31:15: warning: unused variable ‘n’ [-Wunused-variable] long long n; ^ user.cpp:32:37: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cabana.in", "r", stdin); ^ user.cpp:33:39: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("cabana.out", "w", stdout); ^