Compilare: user.cpp: In function ‘void prime(long long int, long int)’: user.cpp:19: warning: comparison between signed and unsigned integer expressions user.cpp: In function ‘int main()’: user.cpp:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result user.cpp:36: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result