foo.cc:10:10: error: redefinition of 'long long int cnt'
   10 | int id=0,cnt,n,m,mod,r;
      |          ^~~
foo.cc:9:118: note: 'long long int cnt' previously declared here
    9 | int a[2000010],head[2000010],to[2000010],ne[2000010],fa[2000010],siz[2000010],dep[2000010],son[2000010],idx[2000010],cnt,top[2000010],num[2000010];
      |                                                                                                                      ^~~

Found 3 testcases.
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