Compilare: user.cpp: In function ‘int main()’: user.cpp:33:13: warning: unused variable ‘j’ [-Wunused-variable] int i,n,j,lg; ^ user.cpp:35:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin, "%d", &n); ^ user.cpp:36:45: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] for(i=1;i<=n;++i) fscanf(fin, "%d", v+i); ^