Compilare: user.cpp: In function ‘int main()’: user.cpp:45:35: warning: format ‘%lf’ expects argument of type ‘double’, but argument 3 has type ‘long double’ [-Wformat=] fprintf(fout, "%lf\n", sum); ^ user.cpp:36:40: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d %d", &n, &x, &y); ^ user.cpp:41:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d %d", &x, &y); ^