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

int n;

struct Node
{
	int color;
	int index;
};

vector<Node> nodes;
vector<vector<int>> groups;
vector<int> avail_colors;

void SetColor(int a, int c)
{
	nodes[a].color = c;
	nodes[a].index = 0;
	groups[c].push_back(a);
}

void Init()
{
	nodes.resize(n);
	groups.resize(n);
	for (int i = 0; i < n; i++)
		SetColor(i, i);
}

void Free(int c)
{
	groups[c].clear();
	avail_colors.push_back(c);
}

void Fill(int a)
{
	int c = nodes[a].color;
	if (c < 0)
		return;
	for (int i : groups[c])
		nodes[i].color = -1;
	Free(c);
}

void Merge(int a, int b)
{
	int ca = nodes[a].color;
	int cb = nodes[b].color;
	if (ca == cb)
		return Fill(a);
	if (groups[ca].size() < groups[cb].size())
		swap(ca, cb);
	for (int i : groups[cb])
	{
		nodes[i].color = ca;
		nodes[i].index = (int) groups[ca].size();
		groups[ca].push_back(i);
	}
	Free(cb);
}

void Add(int a, int b)
{
	if (nodes[a].color < 0)
		Fill(b);
	else if (nodes[b].color < 0)
		Fill(a);
	else if (a == b)
		Fill(a);
	else
		Merge(a, b);
}

void Del(int a)
{
	int c = nodes[a].color;
	if (c >= 0)
	{
		int i = nodes[a].index;
		int b = groups[c].back();
		assert(groups[c].size() >= 2);
		nodes[b].index = i;
		groups[c][i] = b;
		groups[c].pop_back();
	}
	c = avail_colors.back();
	avail_colors.pop_back();
	SetColor(a, c);
}

int Query(int a)
{
	int c = nodes[a].color;
	if (c < 0)
		return 1;
	else if (groups[c].size() > 1)
		return -1;
	else
		return 0;
}

int main()
{
	int q;
	scanf("%d%d", &n, &q);
	Init();
	for (; q; q--)
	{
		char c[8];
		scanf("%s", c);
		if (*c == '+')
		{
			int a, b;
			scanf("%d%d", &a, &b);
			Add(a - 1, b - 1);
		}
		else if (*c == '-')
		{
			int c;
			scanf("%d", &c);
			Del(c - 1);
		}
		else
		{
			int d;
			scanf("%d", &d);
			int r = Query(d - 1);
			if (r < 0)
				putchar('?');
			else
				printf("%d", r);
		}
	}
	putchar('\n');
	return 0;
}