Compilare: main.cpp: In function 'void solve()': main.cpp:39:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0; i<v[nod].size(); i++){ ~^~~~~~~~~~~~~~ main.cpp: In function 'int main()': main.cpp:64:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cmcm.in","r",stdin); ^ main.cpp:65:39: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("cmcm.out","w",stdout); ^