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//Solution by Mikołaj Kołek

#include "bits/stdc++.h"
#define intin *istream_iterator<int>(cin)

using namespace std;

struct FindUnion {
	vector<int> P, R;
	int size;
	
	FindUnion(int size) {
		P = vector<int>(size), R = vector<int>(size);
		iota(P.begin(), P.end(), 0);
		this->size = size;
	}
	
	int find(int v) {
		if(P[v] == v)
			return v;
		
		return P[v] = find(P[v]);
	}
	
	void unify(int a, int b) {
		a = find(a), b = find(b);
		
		if(R[a] > R[b])
			P[b] = a;
		else {
			P[a] = b;
			R[a] += (R[a] == R[b]);
		}
	}
};

int main() {
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	
	int n = intin, q = intin;
	vector<int> state(n);
	FindUnion findUnion(n);
	vector<unordered_set<int>> G(n);
	vector<int> indexInFu(n);
	iota(indexInFu.begin(), indexInFu.end(), 0);
	
	while(q--) {
		char type = *istream_iterator<char>(cin);
		
		if(type == '+') {
			int a = intin - 1, b = intin - 1;
			
			if(state[a] == 1)
				a = b;
			if(state[b] == 1)
				b = a;
			
			if(findUnion.find(indexInFu[a]) != findUnion.find(indexInFu[b])) {
				findUnion.unify(indexInFu[a], indexInFu[b]);
				state[a] = 2;
				state[b] = 2;
				
				G[a].insert(b);
				G[b].insert(a);
			}
			else {
				function<void(int, int)> DFS = [&] (int v, int p) {
					findUnion.P[indexInFu[v]] = indexInFu[v];
					findUnion.R[indexInFu[v]] = 0;
					state[v] = 1;
					
					for(const auto &u : G[v]) {
						if(u == p)
							continue;
						
						DFS(u, v);
					}
					
					G[v] = unordered_set<int>();
				};
				
				DFS(a, -1);
			}
		}
		else if(type == '-') {
			int c = intin - 1;
			
			if(state[c] == 2) {
				int newIndexInFu = findUnion.size++;
				findUnion.P.push_back(newIndexInFu); findUnion.R.push_back(0);
				
				if(G[c].size() == 1) {
					for(const auto &neighbor : G[c]) {
						G[neighbor].erase(c);
						
						if(G[neighbor].empty())
							state[neighbor] = 0;
					}
				}
				else {
					int randomNeighbor = *G[c].begin();
					G[randomNeighbor].erase(c);
					
					for(const auto &neighbor : G[c]) {
						if(neighbor == randomNeighbor)
							continue;
						
						G[neighbor].erase(c);
						G[neighbor].insert(randomNeighbor);
						G[randomNeighbor].insert(neighbor);
					}
				}
				
				G[c] = unordered_set<int>();
				indexInFu[c] = newIndexInFu;
			}
			
			state[c] = 0;
		}
		else if(type == '?') {
			int d = intin - 1;
			cout << (state[d] == 2 ? "?" : to_string(state[d]));
		}
	}
	
	return 0;
}