/in/foo.cc: In function 'int main()':
/in/foo.cc:8:19: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);for(int i=1;i<=n;i++) scanf("%d",&a[i]);
                   ^
/in/foo.cc:8:59: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d",&n);for(int i=1;i<=n;i++) scanf("%d",&a[i]);
                                                           ^