Compilare: user.cpp: In function ‘int main()’: user.cpp:29:15: warning: unused variable ‘nr’ [-Wunused-variable] long long nr,cnr; ^ user.cpp:29:18: warning: unused variable ‘cnr’ [-Wunused-variable] long long nr,cnr; ^ user.cpp:30:27: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf (fin,"%d\n",&t); ^ user.cpp:33:26: warning: ignoring return value of ‘char* fgets(char*, int, FILE*)’, declared with attribute warn_unused_result [-Wunused-result] fgets (s,501,fin); ^