Compilare: user.cpp: In function ‘int read()’: user.cpp:29:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int euler(int)’: user.cpp:63:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int dfs(int)’: user.cpp:78:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int write()’: user.cpp:112:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int read()’: user.cpp:20:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:25:30: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d", &x,&y); ^ user.cpp: In function ‘int main()’: user.cpp:116:27: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(FIN,"r",stdin); ^ user.cpp:117:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen(FOUT,"w",stdout); ^