Compilare: user.cpp: In function ‘int main()’: user.cpp:46:29: warning: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘long long int’ [-Wformat=] fprintf(out, "%d\n", sum); ^ user.cpp:24:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &n); ^ user.cpp:25:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &k); ^ user.cpp:31:29: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(in, "%d", &x); ^