Compilare: user.cpp: In function ‘int add(int, int, int)’: user.cpp:33:1: warning: no return statement in function returning non-void [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:59:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<g[node].size();++i){ ^ user.cpp:85:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<gf[node].size();++i){ ^ user.cpp:94:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<gf[node].size();++i){ ^ user.cpp:42:29: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("egal.in","r",stdin); ^ user.cpp:43:31: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("egal.out","w",stdout); ^ user.cpp:44:15: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&N); ^ user.cpp:46:22: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&x,&y); ^ user.cpp:51:20: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&v[i]); ^