#include<bits/stdc++.h>
using namespace std;

#define ll long long
#define nl "\n"

void files(){
    ios_base::sync_with_stdio(false),cin.tie(NULL),cout.tie(NULL);
    #ifndef ONLINE_JUDGE
        freopen("input.txt", "r", stdin), freopen("output.txt", "w", stdout);
    #endif
}


void solve(){

    int n; cin>>n;
    int s; cin>>s;
    vector<bool> vis(n+1, false);
    stack<int> st;
    vis[s] = true;
    st.push(s);
    int k; cin>>k;
    vector<int> child(k);
    for(int i=0; i<k; i++){
        cin>>child[i];
    }
    vis[child[0]] = true;
    st.push(child[0]);
    bool ok = false;
    while(!st.empty()){
        int x = st.top();
        cout<<"> "<<x<<endl;
        cout.flush();
        cin>>k;
        if(k<=0) return;
        child = vector<int>();
        for(int i=0; i<k; i++){
            int y; cin>>y;
            if(!vis[y]){
                child.push_back(y);
            }
        }
        if(child.size() == 0){
            st.pop();
            continue;
        }
        vis[child[0]] = true;
        st.push(child[0]);
    }
}

int main(){
    files();
    int t = 1;
    // cin>>t;
    while(t--) solve();

    return 0;
}