/in/foo.cc: In function 'll calc(int, ll, ll)':
/in/foo.cc:32:51: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
 inline ll calc(int u,ll s,ll h){return ch[u][1]?(s-h<<1):((a[u]<<1)>s?(s-a[u]<<1):s-1);}
                                                  ~^~
/in/foo.cc:32:73: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
 inline ll calc(int u,ll s,ll h){return ch[u][1]?(s-h<<1):((a[u]<<1)>s?(s-a[u]<<1):s-1);}
                                                                        ~^~~~~
/in/foo.cc: In function 'void rot(int)':
/in/foo.cc:38:28: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
     if(ch[fa][d]=ch[o][d^1])f[ch[fa][d]]=fa;
                            ^
/in/foo.cc: In function 'void dfs(int)':
/in/foo.cc:58:34: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
     ans+=(maxn<<1)>sum[u]?(sum[u]-maxn<<1):sum[u]-1;
                            ~~~~~~^~~~~
/in/foo.cc: In function 'int main()':
/in/foo.cc:94:12: error: too many arguments to function 'void dfs(int)'
     dfs(1,0);
            ^
/in/foo.cc:49:6: note: declared here
 void dfs(int u){
      ^~~