Compilare: user.cpp: In function ‘void redirectInput(const char*, const char*)’: user.cpp:10: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:11: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp: In function ‘void solve()’: user.cpp:58: warning: format ‘%lu’ expects type ‘long unsigned int’, but argument 2 has type ‘size_t’ user.cpp:34: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result