Compilare: user.cpp: In function ‘int main()’: user.cpp:46:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<v[1].size(); i++) ^ user.cpp:68:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (i=0; i<v[nod].size(); i++) ^ user.cpp:31:32: 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:32:34: 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:33:24: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d",&n,&m); ^ user.cpp:37:33: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d",&a,&b,&c); ^