/in/foo.cc: In function 'int main()':
/in/foo.cc:6:14: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
 scanf("%d",&n);//错误的输入居然能过，如果改成“%lld”不能过，必须用%d才能过，，，，醉了
              ^