Compilare: main.cpp: In function 'int main()': main.cpp:27:29: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lca.in","r",stdin); ^ main.cpp:28:31: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("lca.out","w",stdout); ^ main.cpp:29:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m);++m; ^ main.cpp:31:72: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d", &nr),tata[i]=nr,arb[nr].push_back(i),arb[i].push_back(nr); ^ main.cpp:37:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &nr1, &nr2); ^