Compilare: user.cpp: In function ‘int main()’: user.cpp:29:22: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%d",&n); ^ user.cpp:31:39: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%ld%ld",&a[i],&b[i]); ^