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#include <ranges>
#include <vector>
#include <iostream>
#include <numeric>
#include <algorithm>
#include <unordered_map>
#include <set>
#include <stack>

using namespace std;

int main() {
    ios_base::sync_with_stdio(false);

    int n;
    cin >> n;

    int no_atom_edges;
    cin >> no_atom_edges;

    set<pair<int, int>> atom_edges;
    vector<vector<int>> atom(n + 1);
    vector<vector<int>> target(n + 1);

    int a, b;
    for (int i = 0; i < no_atom_edges; i++) {
        cin >> a >> b;
        atom_edges.insert(make_pair(min(a, b), max(a, b)));
        atom[a].push_back(b);
        atom[b].push_back(a);
    }

    int no_target_edges;
    cin >> no_target_edges;

    set<pair<int, int>> target_edges;
    for (int i = 0; i < no_target_edges; i++) {
        cin >> a >> b;
        target_edges.insert(make_pair(min(a, b), max(a, b)));
        target[a].push_back(b);
        target[b].push_back(a);
    }

    vector<pair<int, int>> add_instructions;
    vector<pair<int, int>> remove_instructions;

    set<int> seen;
    stack<int> stack;

    // run DFS for atom from vertex 1
    stack.push(1);
    seen.insert(1);

    vector<int> atom_dfs_order;

    while (!stack.empty()) {
        auto curr = stack.top();
        stack.pop();
        atom_dfs_order.push_back(curr);

        for (const auto &nei: atom[curr]) {
            if (seen.find(nei) == seen.end()) {
                stack.push(nei);
                seen.insert(nei);
            }
        }
    }

    // add edge 1--x for all vertices x in G in DFS order
    for (const auto &item: atom_dfs_order) {
        auto edge = make_pair(1, item);
        if (atom_edges.find(edge) == atom_edges.end() && edge.second != 1) {
            add_instructions.push_back(edge);
        }
    }

    // add missing (present in target, missing in atom)
    for (const auto &target_edge: target_edges) {
        if (atom_edges.find(target_edge) == atom_edges.end() && target_edge.first != 1) {
            add_instructions.push_back(target_edge);
        }
    }

    // remove missing (present in atom, missing in target)
    for (const auto &atom_edge: atom_edges) {
        if (target_edges.find(atom_edge) == target_edges.end() && atom_edge.first != 1) {
            remove_instructions.push_back(atom_edge);
        }
    }

    // run DFS for target from vertex 1
    seen.clear();
    stack.push(1);
    seen.insert(1);

    vector<int> target_dfs_order;

    while (!stack.empty()) {
        auto curr = stack.top();
        stack.pop();
        target_dfs_order.push_back(curr);

        for (const auto &nei: target[curr]) {
            if (seen.find(nei) == seen.end()) {
                stack.push(nei);
                seen.insert(nei);
            }
        }
    }

    // remove edge 1--x for all x in G in reverse DFS order (if not present in target)
    for (int &it: std::ranges::reverse_view(target_dfs_order)) {
        auto edge = make_pair(1, it);
        if (target_edges.find(edge) == target_edges.end() && edge.second != 1) {
            remove_instructions.push_back(edge);
        }
    }

    cout << add_instructions.size() + remove_instructions.size() << endl;
    for (const auto &instruction: add_instructions) {
        cout << "+ " << instruction.first << " " << instruction.second << endl;
    }

    for (const auto &instruction: remove_instructions) {
        cout << "- " << instruction.first << " " << instruction.second << endl;
    }

    return 0;
}