/in/foo.cc: In function 'll calc(int, ll, ll)':
/in/foo.cc:38:51: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   38 | 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);}  //计算冲突值
      |                                                  ~^~
/in/foo.cc:38:73: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   38 | 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);}  //计算冲突值
      |                                                                        ~^~~~~
/in/foo.cc: In function 'void rot(int)':
/in/foo.cc:44:17: warning: suggest parentheses around assignment used as truth value [-Wparentheses]
   44 |     if(ch[fa][d]=ch[o][d^1])f[ch[fa][d]]=fa;
      |        ~~~~~~~~~^~~~~~~~~~~
/in/foo.cc: In function 'void work(int)':
/in/foo.cc:64:34: warning: suggest parentheses around '-' inside '<<' [-Wparentheses]
   64 |     ans+=(maxn<<1)>sum[u]?(sum[u]-maxn<<1):sum[u]-1;
      |                            ~~~~~~^~~~~