Compilare: user.cpp: In function ‘long int tr(long int)’: user.cpp:17:1: warning: control reaches end of non-void function [-Wreturn-type] } ^ user.cpp: In function ‘int main()’: user.cpp:51:25: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(f,"%ld\n",&N); ^ user.cpp:52:53: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(long int i=1;i<=N;i++) fscanf(f,"%ld",&v[i]); ^