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#include <bits/stdc++.h>

using namespace std;

int states[1300070];
int amountOfQueries;
int amountOfPeople;

int parents[1300070];
set<int> children[1300070];

int mapping[1300070];
int sizes[1300070];

int nextMapping = 300007;

void makeSet(int node)
{
    parents[node] = node;
    sizes[node] = 1;
}
int findSet(int node)
{
    if (node == parents[node])
        return node;
    parents[node] = findSet(parents[node]);
    return parents[node];
}
void unionSets(int a, int b)
{
    a = findSet(a);
    b = findSet(b);
    if (parents[a] != parents[b])
    {
        parents[b] = a;
        children[a].insert(b);
        sizes[a] += sizes[b];
    }
}
void dfs(int node)
{
    states[node] = 1;
    makeSet(node);
    for (int child : children[node])
    {
        dfs(child);
    }
    children[node].clear();
}
void dfs2(int node)
{
    states[node] = 0;
    makeSet(node);
    for (int child : children[node])
    {
        dfs2(child);
    }
}
int main()
{
    ios_base::sync_with_stdio(false);
    cin.tie(0);

    cin >> amountOfPeople >> amountOfQueries;

    for (int i = 1; i <= amountOfPeople; ++i)
    {   
        mapping[i] = i;
        makeSet(i);
    }

    for (int q = 0; q < amountOfQueries; ++q)
    {
        char type;
        cin >> type;

        if (type == '+')
        {
            int first, second;
            cin >> first >> second;
            first = mapping[first];
            second = mapping[second];

            if (states[first] == 1)
            {
                states[second] = 1;
                unionSets(first, second);
            }
            if (states[second] == 1)
            {
                states[first] = 1;
                unionSets(first, second);
            }

            int firstSet = findSet(first);
            int secondSet = findSet(second);
            if ((states[first] != 1 || states[first] != 1) && firstSet != secondSet)
            {
                unionSets(first, second);
                states[first] = -1;
                states[second] = -1;
            }
            else
            {
                dfs(firstSet);
            }
        }
        else if (type == '-')
        {
            int point;
            cin >> point;
            int mappedPoint = mapping[point];
            int representative = findSet(mappedPoint);
            if (sizes[representative] == 2)
            {
                dfs2(representative);
            }
            else
            {
                sizes[representative] -= 1;
            }
            mapping[point] = nextMapping;
            ++nextMapping;
            mappedPoint = mapping[point];
            states[mappedPoint] = 0;
            makeSet(mappedPoint);
        }
        else
        {
            int point;
            cin >> point;
            point = mapping[point];
            if (states[point] == -1)
            {
                cout << '?';
            }
            else
            {
                cout << states[point];
            }
        }
    }
    cout << '\n';
}