Compilare: user.cpp: In function ‘int main()’: user.cpp:21:28: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d%d",&N,&M); ^ user.cpp:24:63: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(IN,"%d%d%d",&v[i].first,&v[i].second,&v[i].sum); ^