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#include <iostream>

using namespace std;

class find_union {
    int ID;
    int depth;
    find_union* parent;
    int size;
    int comp_count;

    public:
    find_union* go_up() {
        find_union* curr = this;
        while(curr->parent != NULL) {
            curr = curr->parent;
        }
        return curr;
    }

    void unionize(find_union* other) {
        if(equivalent(other)) {
            go_up()->comp_count += 1;
            return;
        }

        find_union* root1 = go_up();
        find_union* root2 = other->go_up();
        if(root1->depth > root2->depth) {
            root2->parent = root1;
            root1->comp_count += root2->comp_count + 1;
            root1->size += root2->size;
        } else {
            root1->parent = root2;
            if(root1->depth < root2->depth) {
                root2->depth += 1;
            }
            root2->comp_count += root1->comp_count + 1;
            root2->size += root1->size;
        }
    }

    bool equivalent(find_union* other) {
        return find() == other->find();
    }

    int has_comp() {
        find_union* root = go_up();
        //cout << "MY ID: " << ID << ", root ID: " << root->ID << "\n";
        //cout << "comp_count: " << root->comp_count << ", size: " << root->size << "\n";
        if(root->comp_count == 0) return 0;
        if(root->comp_count == root->size) return 1;
        return -1;
    }

    int find() {
        find_union* curr = this;
        while(curr->parent != NULL) {
            /* cout << "LOOP\n";
            if(curr == curr->parent) {
                cout << "I AM MY FATHER\n";
            } */
            curr = curr->parent;
        }
        return curr->ID;
    }

    void remove_el() {
        find_union* root = go_up();
        root->comp_count -= 1;
        root->size -= 1;
    }
 
    find_union(int id) {
        ID = id;
        depth = 0;
        parent = NULL;
        size = 1;
        comp_count = 0;
    }

};

void add_comp(int a, int b, int* ID, find_union** tab) {
    if(tab[a] == nullptr) {
        tab[a] = new find_union(*ID);
        *ID += 1;
    }
    if(tab[b] == nullptr) {
        tab[b] = new find_union(*ID);
        *ID += 1;
    }
    tab[a]->unionize(tab[b]);
}

void remove_comp(int a, find_union** tab) {
    tab[a]->remove_el();
    tab[a] = nullptr;
}

int has_comp(int a, find_union** tab) { //1 - yes, 0 - no, -1 - don't know
    if(tab[a] == nullptr) return 0;
    //cout << " [a = " << a + 1<< "] ";
    return tab[a]->has_comp();
}

int main() {
    ios_base::sync_with_stdio(false);
    cin.tie(NULL);

    int n, q;
    cin >> n;
    cin >> q;

    find_union** tab = new find_union*[n];
    for(int i = 0; i < n; ++i) {
        tab[i] = nullptr;
    }

    int curr_ID = 0;
    char c;
    int a, b;
    int ans;
    for(int i = 0; i < q; ++i) {
        cin >> c;
        if(c == '+') {
            cin >> a;
            cin >> b;
            --a;
            --b;
            add_comp(a, b, &curr_ID, tab);
        } else if(c == '-') {
            cin >> a;
            --a;
            remove_comp(a, tab);
        } else { // '?'
            cin >> a;
            --a;
            ans = has_comp(a, tab);
            if(ans == -1) cout << "?";
            else cout << ans;
        }
    }
    cout << "\n";

    return 0;
}