https://www.acwing.com/activity/content/problem/content/1583/

 #include<bits/stdc++.h>
using namespace std;
#define endl '\n'
const int N=30010;
int n,p[N],len[N],siz[N];
//len[i],i到根节点距离
//siz[i],i节点后面跟的节点数量(包括自己)
int find(int x){
    if(x!=p[x]){
        int u=find(p[x]);
        len[x]+=len[p[x]];
        p[x]=u;
    }
    return p[x];
}
void solve()
{   cin>>n;
    for(int i=1;i<N;i++) {p[i]=i;siz[i]=1;}
    while(n--){
        char s;int z,y;
        cin>>s>>z>>y;
        int tz=find(z),ty=find(y);
        if(s=='M'){//让z跟在y后面
            if(tz==ty) continue;
            p[tz]=ty;
            len[tz]=siz[ty];//tz到根节点距离变成ty后面数量
            siz[ty]+=siz[tz];//ty节点后面数量加上tz
        }else{
            if(tz!=ty){cout<<"-1\n";continue;}
        int ti=max(abs(len[z]-len[y])-1,0);
        cout<<ti<<endl;
        }
    }
}
signed main()
{
    ios::sync_with_stdio(false);
cin.tie(0),cout.tie(0);

    solve();



    return 0;
}