Compilare: user.cpp: In function ‘void precompute()’: user.cpp:10: warning: unused variable ‘j’ user.cpp: In function ‘void solve()’: user.cpp:39: warning: unused variable ‘v1’ user.cpp:39: warning: unused variable ‘v2’ user.cpp:39: warning: unused variable ‘v’ user.cpp: In function ‘int main()’: user.cpp:57: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:58: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result user.cpp:59: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result