Compilare: main.cpp: In function 'int main()': main.cpp:18:34: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ubuntzei.in","r",stdin); ^ main.cpp:19:36: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("ubuntzei.out","w",stdout); ^ main.cpp:20:29: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &n, &m, &k); ^ main.cpp:22:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &nr),v[nr]=i; ^ main.cpp:24:95: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d%d", &nr, &nr1, &nr2),graf[nr].push_back({nr1,nr2}),graf[nr1].push_back({nr,nr2}); ^