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#include <iostream>
#include <vector>
#include <algorithm>
#include <set>
#include <utility>
#include <array>

using namespace std;

void input(int & n, int & m_start, vector<vector<int>> & start_neigh, set<pair<int,int>> & cur_set, 
            int & m_dest, vector<vector<int>> & dest_neigh, set<pair<int,int>> & dest_set) {
    cin >> n;
    start_neigh.resize(n, vector<int>());
    dest_neigh.resize(n, vector<int>());
    cin >> m_start;
    for(int i = 0; i < m_start; i++) {
        int a, b;
        cin >> a >> b;
        a--;
        b--;
        if(a > b){
            swap(a, b);
        }
        start_neigh[a].push_back(b);
        start_neigh[b].push_back(a);
        cur_set.insert({a,b});
    }
    cin >> m_dest;
    for(int i = 0; i < m_dest; i++) {
        int a, b;
        cin >> a >> b;
        a--;
        b--;
        if(a > b){
            swap(a, b);
        }
        dest_neigh[a].push_back(b);
        dest_neigh[b].push_back(a);
        dest_set.insert({a,b});
    }
}

void start_dfs(int const ver, vector<vector<int>> const & start_neigh, set<pair<int,int>> & cur_set, vector<array<int,3>> & moves, vector<bool> & visited) {
    if(ver != 0 && cur_set.count({0,ver}) == 0) {
        cur_set.insert({0,ver});
        moves.push_back({0,ver,1});
    }
    visited[ver] = 1;
    for(auto const neigh : start_neigh[ver]) {
        if(!visited[neigh]) {
            start_dfs(neigh, start_neigh, cur_set, moves, visited);
        }
    }
}

void dest_dfs(int const ver, vector<vector<int>> const & dest_neigh, set<pair<int,int>> & cur_set, vector<array<int,3>> & moves, vector<bool> & visited, vector<pair<int,int>> & dest_stack) {
    if(ver != 0) {
        dest_stack.push_back({0,ver});
    }
    visited[ver] = 1;
    for(auto const neigh : dest_neigh[ver]) {
        if(!visited[neigh]) {
            dest_dfs(neigh, dest_neigh, cur_set, moves, visited, dest_stack);
        }
    }
}

void solve() {
    int n;
    int m_start;
    vector<vector<int>> start_neigh;
    set<pair<int,int>> cur_set;
    int m_dest;
    vector<vector<int>> dest_neigh;
    set<pair<int,int>> dest_set;
    input(n, m_start, start_neigh, cur_set, m_dest, dest_neigh, dest_set);

    vector<array<int,3>> moves;

    vector<bool> visited(n, 0);
    start_dfs(0, start_neigh, cur_set, moves, visited);

    for(auto const e : dest_set) {
        if(cur_set.count(e) == 0) {
            cur_set.insert(e);
            moves.push_back({e.first,e.second,1});
        }
    }

    vector<pair<int,int>> dest_stack;
    fill(visited.begin(), visited.end(), 0);
    dest_dfs(0, dest_neigh, cur_set, moves, visited, dest_stack);

    vector<pair<int,int>> to_remove;
    for(auto const e : cur_set) {
        if(e.first != 0 && dest_set.count(e) == 0) {
            to_remove.push_back(e);
        }
    }
    for(auto const e : to_remove) {
        moves.push_back({e.first,e.second,-1});
    }

    for(int i = dest_stack.size() - 1; i >= 0; i--) {
        if(dest_set.count(dest_stack[i]) == 0) {
            moves.push_back({dest_stack[i].first,dest_stack[i].second,-1});
        }
    }

    cout << moves.size() << "\n";
    for(auto const i : moves) {
        if(i[2] == 1) {
            cout << "+ ";
        } else if(i[2] == -1) {
            cout << "- ";
        }
        cout << i[0] + 1 << " " << i[1] + 1 << "\n";
    }
}

int main(){
    ios_base::sync_with_stdio(0);
    cin.tie(0);

    solve();

    return 0;
}