Compilare: user.cpp: In function ‘void build(int, int, int, FILE*)’: user.cpp:15:39: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%lld",&arb[nod].min); ^ user.cpp: In function ‘int main()’: user.cpp:64:36: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("biscuiti.in","r",stdin); ^ user.cpp:65:38: warning: ignoring return value of ‘FILE* freopen(const char*, const char*, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] freopen("biscuiti.out","w",stdout); ^ user.cpp:66:18: warning: ignoring return value of ‘int scanf(const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] scanf("%d",&n); ^