Compilare: user.cpp: In function ‘int main()’: user.cpp:41:59: warning: format ‘%lld’ expects argument of type ‘long long int’, but argument 3 has type ‘int’ [-Wformat=] fprintf( output_file, "%lld\n", solve( (1 << N) - 1 ) ); ^ user.cpp:33:35: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf( input_file, "%d", &N ); ^ user.cpp:36:42: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf( input_file, "%d", &V[i] ); ^