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

vector<unordered_set<int>> groups;
int nextFreeSetID = 0;
int knowledge[300001]; // node knowledge status. 2 = UNKNOWN
int membership[300001];
int fusedInto[2000001]; // basically a find-union of groups

void newGroup(int, int);
void groupAdd(int, int);
void groupRemove(int);
void joinGroups(int, int);
void knowAll(int);
int getGroupID(int);
int getRealGroupID(int);


// create new group including a and b and return its ID
void newGroup(int a, int b) {
    membership[a] = nextFreeSetID;
    membership[b] = nextFreeSetID;
    knowledge[a] = 2;
    knowledge[b] = 2;
    unordered_set<int> setty{a, b};
    groups.push_back(setty);
    fusedInto[nextFreeSetID] = nextFreeSetID;
    nextFreeSetID++;
}

// add B to A's group
void groupAdd(int a, int b) {
    int gid = getGroupID(a);
    groups[gid].insert(b);
    membership[b] = gid;
    knowledge[b] = 2;
}

// remove A from its group
// if only 1 is left, dissolve group
void groupRemove(int a) {
    if (knowledge[a] == 2) {
        int gid = getGroupID(a);
        groups[gid].erase(a);
        if (groups[gid].size() == 1) {
            for (int i : groups[gid]) {
                knowledge[i] = 0;
            }
            // not sure if this is needed and might be slow tbh
//            fusedInto[gid] = -1;
//            groups[gid].clear();
        }
    }
    knowledge[a] = 0;
}

// joins A's and B's groups
// if they are the same groups,
void joinGroups(int a, int b) {
    int groupA = getGroupID(a);
    int groupB = getGroupID(b);
    if (groupA == groupB) {
        knowAll(a);
    } else {
//        cout << "JOINING GROUP " << groupA << " AND GROUP " << groupB << endl;
//        cout << "SIZES: " << groups[groupA].size() << " | " << groups[groupB].size() << endl;
        if (groups[groupA].size() > groups[groupB].size()) {
            groups[groupA].insert(groups[groupB].begin(), groups[groupB].end());
            fusedInto[groupB] = groupA;
//            groups[groupB].clear();
        } else {
            groups[groupB].insert(groups[groupA].begin(), groups[groupA].end());
            fusedInto[groupA] = groupB;
//            groups[groupA].clear();
        }
    }
}

// dissolves A's group
// sets knowledge of all members to 1
void knowAll(int a) {
    int gid = getGroupID(a);
    for (int i : groups[gid]) {
        knowledge[i] = 1;
    }
    // not sure if this is needed and might be slow tbh
    //    fusedInto[gid] = -1;
    //    groups[gid].clear();
}

// return ID of A's group
int getGroupID(int a) {
    int gid = getRealGroupID(membership[a]);
    membership[a] = gid;
    return gid;
}

// get group ID of g after fuses
int getRealGroupID(int g) {
    if (fusedInto[g] == g) {
        return g;
    } else {
        int realGroup = getRealGroupID(fusedInto[g]);
        fusedInto[g] = realGroup;
        return realGroup;
    }
}

int main() {
    int n, q;
    scanf("%d %d\n", &n, &q);
    char c;
    int a, b;
    for (int i = 0; i < q; ++i) {
//        cout << "PRINT ALL GROUPS" << endl;
//        for (int k = 0; k < nextFreeSetID; ++k) {
//            if (fusedInto[k] == k) {
//                cout << "GROUP " << k << endl;
//                for (int j : groups[k]) {
//                    cout << j << " ";
//                }
//                cout << endl;
//            }
//        }
//        cout << "PRINTED ALL GROUPS" << endl;
        scanf("%c", &c);
        if (c == '?') {
            scanf("%d\n", &a);
            if (knowledge[a] < 2) {
                printf("%d", knowledge[a]);
            } else {
                printf("\?");
            }
        } else if (c == '+') {
            scanf("%d %d\n", &a, &b);
            if (a == b) {
                if (knowledge[a] == 0) {
                    knowledge[a] = 1;
                } else /* knowledge[a] == 2 */ {
                    knowAll(a);
                }
            }
            if (knowledge[a] < knowledge[b]) {
                // eliminate symmetrical cases
                int temp = a;
                a = b;
                b = temp;
            }
            if (knowledge[a] == 0) /* and knowledge[b] == 0 */ {
                newGroup(a, b);
            } else if (knowledge[a] == 1) {
                if (knowledge[b] == 0) {
                    knowledge[b] = 1;
                } else {
                    // THIS SHOULD NEVER HAPPEN!
                }
            } else /* knowledge[a] == 2 */ {
                if (knowledge[b] == 0) {
                    groupAdd(a, b);
                } else if (knowledge[b] == 1) {
                    knowAll(a);
                } else {
                    // both A and B unknown.
                    joinGroups(a, b);
                }
            }
        } else if (c == '-') {
            scanf("%d\n", &a);
            groupRemove(a);
        }
    }

    printf("\n");

    return 0;
}