Compilare: user.cpp: In function ‘void euler(int)’: user.cpp:10:25: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(i<v[nod].size()) ^ user.cpp:15:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<v[x].size();j++) ^ user.cpp: In function ‘int main()’: user.cpp:51:37: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j=0;j<v[x].size();j++) ^ user.cpp:28:39: 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:29:41: 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:30:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:33:29: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&x,&y); ^