answer.code: In function ‘auto varray(const T&, const int&, const Args& ...)’:
answer.code:70:107: error: missing template arguments before ‘(’ token
   70 | template<class T,class ...Args> auto varray(const T &x,const int &len,const Args &...args) { return vector(len+2,varray<ll>(x,args...)); }
      |                                                                                                           ^
answer.code: In function ‘void _main()’:
answer.code:117:32: warning: format ‘%d’ expects argument of type ‘int’, but argument 2 has type ‘ll’ {aka ‘long long int’} [-Wformat=]
  117 |                 printf("Case #%d: %s\n",t,diff(sum*2,(ll)n*n)<0.02?"GOOD":"BAD");
      |                               ~^        ~
      |                                |        |
      |                                int      ll {aka long long int}
      |                               %lld
answer.code:111:14: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  111 |         scanf("%d",&T);
      |         ~~~~~^~~~~~~~~
answer.code:113:22: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  113 |                 scanf("%d",&n);
      |                 ~~~~~^~~~~~~~~
answer.code:114:32: warning: ignoring return value of ‘int scanf(const char*, ...)’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
  114 |                 fo(i,1,n) scanf("%d",&p[i]);
      |                           ~~~~~^~~~~~~~~~~~