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#include <bits/stdc++.h>
using namespace std;
bool odw[300001];
int stan[300001],rep[300001],ile[300001];
vector<int>pol[300001];
int find(int a){
	if(rep[a]!=a)rep[a]=find(rep[a]);
	return rep[a];
}
void onion(int a,int b){
	a=find(a);b=find(b);
	if(ile[b]>ile[a])swap(a,b);
	ile[a]+=ile[b];
	rep[b]=a;
}
void dfs(int w){
	odw[w]=1;
	ile[w]=1;
	rep[w]=w;
	for(int i=(int)pol[w].size()-1;i>=0;--i){
		if(!odw[pol[w][i]]){
			stan[pol[w][i]]=1;
			dfs(pol[w][i]);
		}
		pol[w].pop_back();
	}
	odw[w]=0;
}
int main(){
	ios_base::sync_with_stdio(0);
	cin.tie(0);
	int n,q,a,b;
	char c;
	cin>>n>>q;
	for(int i=1;i<=n;++i){rep[i]=i;ile[i]=1;}
	for(int i=0;i<q;++i){
		cin>>c;
		if(c=='-'){
			cin>>a;
			stan[a]=0;
			dfs(a);
		}
		else if(c=='+'){
			cin>>a>>b;
			if(find(a)==find(b)){
				stan[a]=1;
				dfs(a);
			}
			else{
				if(stan[a]==1)stan[b]=1;
				if(stan[b]==1)stan[a]=1;
				if(stan[a]!=1){stan[a]=2;stan[b]=2;}
				onion(a,b);
				pol[a].emplace_back(b);
				pol[b].emplace_back(a);
			}
		}
		else{
			cin>>a;
			if(stan[a]==2)cout<<'?';
			else cout<<stan[a];
		}
	}
}