Compilare: user.cpp: In function ‘int main()’: user.cpp:23:10: warning: statement has no effect [-Wunused-value] for(n;n>0;n--){ ^ user.cpp:22:26: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%lld",&n); ^ user.cpp:24:37: warning: ignoring return value of ‘int fscanf(FILE*, const char*, ...)’, declared with attribute warn_unused_result [-Wunused-result] fscanf(fin,"%lld%lld",&a,&b); ^