14/40

class V():
    def __init__(self, id):
        self.id = id
        self.nodes = []
        self.node_type = []

    def add_edge(self, v, type):
        self.nodes.append(v)
        self.node_type.append(type)

    def get_nodes(self):
        return self.nodes, self.node_type

def n_dfs(v, vs):
    global used
    global gr
    global ans
    used[v] = True
    nodes, node_type = gr[v].get_nodes()

    for i in range(0, len(nodes)):

        if(nodes[i] == vs):
            if(node_type[i] == '+'):
                ans = '-'
                return '-'

        if(not used[nodes[i]]):
            if(node_type[i] == '+'):
                n_dfs(nodes[i], vs)

    if(ans == '-'):
        return '-'

    return '?'

def dfs(v, vs):
    global used
    global gr
    global ans
    used[v] = True
    nodes, node_type = gr[v].get_nodes()

    for i in range(0, len(nodes)):
        if(nodes[i] == vs):
            if(node_type[i] == '+'):
                ans = '+'
                return '+'
            elif(node_type[i] == '-'):
                ans = '-'
                return '-'

        if(not used[nodes[i]]):
            if(node_type[i] == '+'):
                dfs(nodes[i], vs)
            elif(node_type[i] == '-'):
                n_dfs(nodes[i], vs)

    if(ans == '+'):
        return '+'
    elif(ans == '-'):
        return '-'

    return '?'

n, k = list(map(str, input().strip().split(' ')))
gr = []

for i in range(0, int(n)):
            gr.append(V(i))

for i in range(0, int(k)):
    z, v1, v2 = list(map(str, input().strip().split(' ')))

    v1 = int(v1)
    v2 = int(v2)
    v1 -= 1
    v2 -= 1

    if(z == '+'):
        gr[v1].add_edge(v2, '+')
        gr[v2].add_edge(v1, '+')
    elif(z == '-'):
        gr[v1].add_edge(v2, '-')
        gr[v2].add_edge(v1, '-')
    elif(z == '?'):
        used = []
        for i in range(0, int(n)):
            used.append(False)
        ans = ''
        print(dfs(v1, v2))