Compilare: user.cpp: In function ‘void Euler_Tour(int)’: user.cpp:39:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 0 ; i < G[nod].size() ; i ++ ) { ^ user.cpp: In function ‘void Read()’: user.cpp:24:31: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , &n , &m ); ^ user.cpp:27:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d\n" , &v[i] ); ^ user.cpp:28:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%s\n" , s ); ^ user.cpp: In function ‘void Solve()’: user.cpp:99:39: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ( "%d%d" , &a , &b ); ^ user.cpp: In function ‘int main()’: user.cpp:112:30: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(IN , "r" , stdin); ^ user.cpp:113:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(OUT , "w" , stdout); ^