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#include <bits/stdc++.h>

using namespace std;

typedef long long ll;
typedef long double ld;
typedef vector<int> vi;
typedef pair<int, int> pii;

#define FOR(x, b, e) for(int x = (b); x <= (e); ++(x))
#define FORD(x, b, e) for(int x = (b); x >= (e); --(x))
#define REP(x, n) for(int x = 0; x < (n); ++x)
#define ALL(c) (c).begin(), (c).end()
#define SIZE(x) ((int)(x).size())
#define FOREACH(a, b) for (auto&a : (b))
#define PB push_back
#define PF push_front
#define MP make_pair
#define ST first
#define ND second
#define DBG(vari) cerr<<#vari<<" = "<<(vari)<<endl;

template <typename T>
std::ostream& operator<<(std::ostream &output, const vector<T> &vec)
{
    output << "[";
    FOREACH(x, vec) output << x << ", ";
    output << "]";
    return output;
}

template <typename T, typename U>
std::ostream& operator<<(std::ostream &output, const pair<T,U> &p)
{
    output << "(";
    output << p.ST << ", " << p.ND;
    output << ")";
    return output;
}

typedef vector<vi> graph;

class FindUnion {
  vector<int> p;
  vector<int> size;
  vector<int> reals;

  public:
    FindUnion(): p(), size(), reals() {}

    void resize(int n) {
      p.resize(n);
      size.resize(n, 1);
      reals.resize(n, 1);
      REP(i, n) {
        p[i] = i;
      }
    }

    int find(int x) {
      if (p[x] == x)
        return x;
      p[x] = find(p[x]);
      return p[x];
    }

    void conn(int a, int b) {
      auto pa = find(a);
      auto pb = find(b);

      if (pa == pb) return;

      if (size[pa] > size[pb]) {
        p[pb] = pa;
        size[pa] += size[pb];
        reals[pa] += reals[pb];
      }
      else
      {
        p[pa] = pb;
        size[pb] += size[pa];
        reals[pb] += reals[pa];
      }
    }

    void dec(int a) {
      reals[find(a)]--;
    }

    int realsize(int a) {
      return reals[find(a)];
    }
};

graph G;
vi x;
FindUnion fu;
int ctr;
vi idx;
vi what;

void dfs(int n, int v=1) {
  x[n] = v;  
  FOREACH(w, G[n]) {
    if (x[w] != v)
      dfs(w, v);
  }
  G[n].clear();
}

int main() {
  ios_base::sync_with_stdio(false);
  cin.tie(NULL);

  int N, Q; cin >> N >> Q;
  G.resize(N+Q+10);
  fu.resize(N+Q+10);
  x.resize(N+Q+10, 0); 
  idx.resize(N+1); iota(ALL(idx), 0);
  ctr = N + 1;

  while (Q--) {
    char cmd; cin >> cmd; 
    if (cmd == '+') {
      int a, b; cin >> a >> b;
      a = idx[a]; b = idx[b];
      
      if (fu.find(a) == fu.find(b)) {
        dfs(a);
      }
      else if (x[a] == 1 || x[b] == 1)
      {
        if (x[a] == 1)
          dfs(b);
        else
          dfs(a);
      }
      else
      {
        G[a].PB(b);
        G[b].PB(a);
        fu.conn(a, b);
        x[a] = -1;
        x[b] = -1;
      }
    }
    else if (cmd == '?') {
      int a; cin >> a;
      a = idx[a];
      if (x[a] == -1)
        cout << '?';
      else
        cout << x[a];
    }
    else if (cmd == '-') {
      int a; cin >> a;
      fu.dec(idx[a]);
      if (fu.realsize(idx[a]) == 1) {
        dfs(idx[a], 0);
      }
      idx[a] = ctr++;
    }
  }
  cout << endl; 
}