Compilare: main.cpp: In function 'int main()': main.cpp:50:35: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("conexidad.in","r",stdin); ^ main.cpp:51:37: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result] freopen("conexidad.out","w",stdout); ^ main.cpp:52:23: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &n, &m); ^ main.cpp:55:28: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result] scanf("%d%d", &nr1, &nr2); ^ main.cpp:74:11: warning: 'poz' may be used uninitialized in this function [-Wmaybe-uninitialized] unionn(poz,i),poz=i; ~~~~~~^~~~~~~