answer.code:1:1: error: ‘CO’ does not name a type
    1 | CO int N=2e5+10;
      | ^~
answer.code:2:1: error: ‘CO’ does not name a type
    2 | CO int64 inf=1e18;
      | ^~
answer.code:4:1: error: ‘vector’ does not name a type
    4 | vector<edge> to[N];
      | ^~~~~~
answer.code:5:8: error: ‘N’ was not declared in this scope
    5 | int fa[N],val[N],siz[N],son[N];
      |        ^
answer.code:5:15: error: ‘N’ was not declared in this scope
    5 | int fa[N],val[N],siz[N],son[N];
      |               ^
answer.code:5:22: error: ‘N’ was not declared in this scope
    5 | int fa[N],val[N],siz[N],son[N];
      |                      ^
answer.code:5:29: error: ‘N’ was not declared in this scope
    5 | int fa[N],val[N],siz[N],son[N];
      |                             ^
answer.code:7:1: error: ‘poly’ does not name a type
    7 | poly f[2][N],g[2][2][N];
      | ^~~~
answer.code:9:1: error: ‘poly’ does not name a type
    9 | poly merge(poly a,poly b){
      | ^~~~
answer.code:24:1: error: ‘poly’ does not name a type
   24 | poly shift(CO poly&a,int64 x){
      | ^~~~
answer.code:29:1: error: ‘poly’ does not name a type
   29 | poly max(CO poly&a,CO poly&b){
      | ^~~~
answer.code: In function ‘void merge_list(int)’:
answer.code:37:9: error: ‘vector’ was not declared in this scope
   37 |         vector<int> s;
      |         ^~~~~~
answer.code:37:16: error: expected primary-expression before ‘int’
   37 |         vector<int> s;
      |                ^~~
answer.code:38:18: error: ‘son’ was not declared in this scope
   38 |         for(;u;u=son[u]) s.push_back(u);
      |                  ^~~
answer.code:38:26: error: ‘s’ was not declared in this scope
   38 |         for(;u;u=son[u]) s.push_back(u);
      |                          ^
answer.code:39:28: error: ‘s’ was not declared in this scope
   39 |         for(int i=0;i<(int)s.size();++i)for(int c=0;c<=1;++c){
      |                            ^
answer.code:40:17: error: ‘g’ was not declared in this scope
   40 |                 g[c][c][i]=f[c][s[i]];
      |                 ^
answer.code:40:28: error: ‘f’ was not declared in this scope
   40 |                 g[c][c][i]=f[c][s[i]];
      |                            ^
answer.code:41:32: error: ‘inf’ was not declared in this scope; did you mean ‘int’?
   41 |                 g[c][c^1][i]={-inf};
      |                                ^~~
      |                                int
answer.code:43:35: error: ‘s’ was not declared in this scope
   43 |         for(int len=2;len/2<=(int)s.size();len<<=1)
      |                                   ^
answer.code:45:25: error: ‘poly’ was not declared in this scope
   45 |                         poly res[2][2];
      |                         ^~~~
answer.code:48:45: error: expected ‘;’ before ‘t’
   48 |                                         poly t=merge(g[a][b][i],g[c][d][i+len/2]);
      |                                             ^~
      |                                             ;
answer.code:49:41: error: ‘res’ was not declared in this scope
   49 |                                         res[a][d]=max(res[a][d],t);
      |                                         ^~~
answer.code:49:65: error: ‘t’ was not declared in this scope
   49 |                                         res[a][d]=max(res[a][d],t);
      |                                                                 ^
answer.code:49:51: error: ‘max’ was not declared in this scope
   49 |                                         res[a][d]=max(res[a][d],t);
      |                                                   ^~~
answer.code:53:59: error: ‘val’ was not declared in this scope
   53 |                                                 t=shift(t,val[s[i+len/2]]);
      |                                                           ^~~
answer.code:53:51: error: ‘shift’ was not declared in this scope
   53 |                                                 t=shift(t,val[s[i+len/2]]);
      |                                                   ^~~~~
answer.code:58:33: error: ‘g’ was not declared in this scope
   58 |                                 g[a][b][i]=res[a][b];
      |                                 ^
answer.code:58:44: error: ‘res’ was not declared in this scope
   58 |                                 g[a][b][i]=res[a][b];
      |                                            ^~~
answer.code: At global scope:
answer.code:62:1: error: ‘poly’ does not name a type
   62 | poly h[2][N];
      | ^~~~
answer.code: In function ‘void merge_son(int)’:
answer.code:65:9: error: ‘vector’ was not declared in this scope
   65 |         vector<int> s;
      |         ^~~~~~
answer.code:65:16: error: expected primary-expression before ‘int’
   65 |         vector<int> s;
      |                ^~~
answer.code:66:13: error: ‘CO’ was not declared in this scope
   66 |         for(CO edge&e:to[u])if(e.v!=fa[u] and e.v!=son[u])
      |             ^~
answer.code:69:9: error: ‘h’ was not declared in this scope
   69 ...