Compilare: user.cpp: In function ‘void APM(int)’: user.cpp:35:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[aux.x].size();++i) ^ user.cpp:50:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[aux.y].size();++i) ^ user.cpp:64:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(SUB.size()==n-1)break; ^ user.cpp: In function ‘int main()’: user.cpp:79:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<G[1].size();++i) ^ user.cpp:90:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<SUB.size();++i) ^ user.cpp:70:32: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.in","r",stdin); ^ user.cpp:71:34: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("apm.out","w",stdout); ^ user.cpp:72:25: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d",&n,&m); ^ user.cpp:75:38: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d %d %d",&x,&y,&cost); ^