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

vector<pair<bool, pair<int, int>>> answer;

int main(){
    ios_base::sync_with_stdio(0);
    cout.tie(0); cin.tie(0);
    int n; cin>>n;
    vector<set<int>> graph(n+1);
    set<pair<int, int>> edges, toadd, todel;
    //-------------------
    int m, u, v; cin>>m;
    while(m--){
        cin>>u>>v; if(u > v) swap(u, v);
        edges.insert({u, v});
        graph[u].insert(v);
        graph[v].insert(u);
    }
    todel = edges;
    //-------------------
    cin>>m;
    while(m--){
        cin>>u>>v; if(u > v) swap(u, v);
        if(edges.count({u, v})) todel.erase({u, v});
        else toadd.insert({u, v});
    }
    //----------------------------------------------
    vector<bool> visited(n+1, 0); visited[1] = 1;
    queue<int> q; q.push(1);
    while(!q.empty()){
        int u = q.front(); q.pop();
        for(auto v: graph[u]){
            if(visited[v]) continue;
            if(!edges.count({1, v})){
                answer.push_back({1, {1, v}});
                graph[1].insert(v); graph[v].insert(1);
                if(!toadd.count({1, v})) todel.insert({1, v});
                else toadd.erase({1, v});
            }
            visited[v] = 1; q.push(v);
        }
    }

    for(auto k: toadd) {answer.push_back({1, {k.first, k.second}}); graph[k.first].insert(k.second); graph[k.second].insert(k.first);};
    set<pair<int, int>> todel2 = todel;
    for(auto k: todel) if(k.first != 1){answer.push_back({0, {k.first, k.second}}); graph[k.first].erase(k.second); graph[k.second].erase(k.first); todel2.erase(k);}

    visited.assign(n+1, 0); q.push(1);
    vector<int> order;
    while(!q.empty()){
        int u = q.front(); q.pop();
        for(auto v: graph[u]){
            if(visited[v]) continue;
            if(todel2.count({u, v})) continue;
            visited[v] = 1; q.push(v);
        }
        order.push_back(u);
    }

    for(int i=(int)(order.size())-1; i>0; i--) if(todel.count({1, order[i]})) answer.push_back({0, {1, order[i]}});
    //-------------------
    cout<<answer.size()<<'\n';
    for(auto &k: answer){
        if(k.first) cout<<"+ "; else cout<<"- ";
        cout<<k.second.first<<' '<<k.second.second<<'\n';
    }
    return 0;
}