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#include <iostream>
#include <vector>
#include <functional>
#include <queue>
#include <utility>
#include <set>
#include <algorithm>

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

    int N;
    std::cin >> N; 

    std::vector<std::vector<int>> G1(N);
    auto G2 = G1;

    std::set<std::pair<int, int>> current_edges, final_edges;
    std::vector<std::tuple<char, int, int>> moves;

    auto exists = [&](auto &edges, int a, int b) {
        return edges.find(std::minmax(a, b)) != edges.end();
    };
    auto add_edge = [&](int a, int b) {
        current_edges.insert(std::minmax(a, b));
        moves.push_back({'+', a+1, b+1});
    };
    auto remove_edge = [&](int a, int b) {
        current_edges.erase(std::minmax(a, b));
        moves.push_back({'-', a+1, b+1});
    };

    auto input_G = [&](auto &G, auto &edges) {
        int M;
        std::cin >> M;
        while(M--) {
            int a, b;
            std::cin >> a >> b;
            a--, b--;
            G[a].push_back(b);
            G[b].push_back(a);
            edges.insert(std::minmax(a, b));
        }
    };
    input_G(G1, current_edges);
    input_G(G2, final_edges);

    auto prep = [&]() {
        std::queue<int> Q;
        std::vector<int> dist(N, -1);

        Q.push(0);
        dist[0] = 0;
        while(Q.size() > 0) {
            int v = Q.front();
            Q.pop();
            
            for(int u : G1[v]) {
                if(dist[u] == -1) {
                    dist[u] = dist[v] + 1;
                    Q.push(u);

                    if(!exists(current_edges, 0, u)) {
                        add_edge(0, u);
                    }
                }
            }
        }
    };
    prep();

    for(auto [a, b] : final_edges) {
        if(!exists(current_edges, a, b)) {
            add_edge(a, b);
        }
    }

    auto remove_excess = [&]() {
        std::vector<std::pair<int, int>> to_remove;
        for(auto [a, b] : current_edges) {
            if(a == 0) {
                continue;
            }
            if(exists(final_edges, a, b)) {
                continue;
            }
            to_remove.push_back({a, b});
        }
        for(auto [a, b] : to_remove) {
            remove_edge(a, b);
        }
    };
    remove_excess();

    auto remove_spanning_tree = [&]() {
        std::queue<int> Q;
        std::vector<int> dist(N, -1);
        std::vector<int> order;

        Q.push(0);
        dist[0] = 0;
        while(Q.size() > 0) {
            int v = Q.front();
            Q.pop();
            order.push_back(v);
            
            for(int u : G2[v]) {
                if(dist[u] == -1) {
                    dist[u] = dist[v] + 1;
                    Q.push(u);
                }
            }
        }

        while(order.size() > 1) {
            int v = order.back();
            order.pop_back();
            
            if(exists(final_edges, 0, v)) {
                continue;
            }
            remove_edge(0, v);
        }
    };
    remove_spanning_tree();

    std::cout << moves.size() << '\n';
    for(auto [c, a, b] : moves) {
        std::cout << c << ' ' << a << ' ' << b << '\n';
    }

    return 0;
}