Compilare: user.cpp: In function ‘int main()’: user.cpp:16:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ciclueuler.in" ,"r", stdin ); ^ user.cpp:17:43: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen ("ciclueuler.out","w", stdout); ^ user.cpp:19:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &nrNodes, &nrEdges); ^ user.cpp:22:40: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf ("%d %d", &node1, &node2); ^