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#include <cstdio>
#include <vector>
using namespace std;

#define FOR(i,a,b) for(int i=(a);i<(b);++i)
#define REP(i,n) FOR(i,0,n)
#define VAR(v,w) __typeof(w) v=(w)
#define FORE(it,c) for(VAR(it,(c).begin());it!=(c).end();++it)
#define PB push_back
#define SIZE(c) ((int)(c).size())
#define MP make_pair
#define FT first
#define SD second
#define INT(x) int x; scanf("%d", &x)
#define STR(n,x) char x[n]; scanf("%s", x)

typedef pair<int,int> PII;
typedef vector<int> VI;
typedef vector<PII> VII;

bool solo[300000], has[300000];
vector<VII> link;
vector<vector<VII> > blink;
vector<VI> life;

PII& getLink(PII v) {
	return link[v.FT][v.SD];
}

vector<PII>& getBlink(PII v) {
	return blink[v.FT][v.SD];
}

int& getLife(PII v) {
	return life[v.FT][v.SD];
}

PII find(PII v) {
	PII r = v;
	while (getLink(r) != r) r = getLink(r);
	while (getLink(v) != r) {
		PII w = getLink(v);
		getLink(v) = r;
		getBlink(r).PB(v);
		v = w;
	}
	return r;
}

PII find(int v) {
	return find(MP(v, SIZE(link[v]) - 1));
}

void unsolo(int v) {
	if (!solo[v]) return;
	link[v].PB(MP(v, SIZE(link[v])));
	blink[v].PB(VII());
	life[v].PB(1);
	solo[v] = 0;
}

void kill(PII v, bool x) {
	if (!solo[v.FT] && v.SD == SIZE(link[v.FT]) - 1) {
		has[v.FT] = x;
		solo[v.FT] = 1;
		if (!x) return;
	}
	vector<PII>& b = getBlink(v);
	FORE(it,b) if (getLink(*it) == v) kill(*it, x);
}

void add(int v, int w) {
	if (has[v]) v = w;
	if (has[w]) w = v;
	if (v == w && solo[v]) {
		has[v] = 1;
		return;
	}
	unsolo(v);
	unsolo(w);
	PII pv = find(v), pw = find(w);
	if (pv == pw)
		kill(pv, 1);
	else {
		getLink(pv) = pw;
		getBlink(pw).PB(pv);
		getLife(pw) += getLife(pv);
	}
}

void take(int v) {
	if (solo[v]) {
		has[v] = 0;
		return;
	}
	has[v] = 0;
	solo[v] = 1;
	PII pv = find(v);
	if (--getLife(pv) == 1) kill(pv, 0);
}

char check(int v) {
	if (has[v]) return '1';
	if (solo[v]) return '0';
	return '?';
}

int main() {
	INT(n);
	INT(q);
	REP(i,n) solo[i] = 1;
	link.resize(n);
	blink.resize(n);
	life.resize(n);
	REP(qq,q) {
		STR(10, op);
		switch (op[0]) {
			case '+': {
				INT(a);
				INT(b);
				--a;
				--b;
				add(a, b);
				break;
			}
			case '-': {
				INT(c);
				--c;
				take(c);
				break;
			}
			default: {
				INT(d);
				--d;
				putchar(check(d));
				break;
			}
		}
	}
	putchar('\n');
}