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

using vasos = std::array<int, 3>;

int main( ) {
    int v, w, n;
    std::scanf("%d%d%d", &v, &w, &n);

    int pos[n + 2];
    for (int i = 1; i <= n; ++i) {
        std::scanf("%d", &pos[i]);
    }
    pos[0] = 0;
    pos[n + 1] = v;

    std::set<vasos> memo;
    std::vector<std::pair<vasos, int>> cola;
    int ini = 0, fin = 1;

    cola.push_back({ { v, 0, 0 }, -1 });

    for (int d = 0; ini != fin; ++d) {
        for (int f = fin; ini != f; ++ini) {
            auto actual = cola[ini];
            if (actual.first[0] == w || actual.first[1] == w || actual.first[2] == w) {
                std::printf("%d\n", d);

                auto temp = actual;
                std::vector<vasos> solucion;

                while (temp.second != -1) {
                    vasos ti = temp.first;
                    solucion.push_back(ti);
                    temp = cola[temp.second];
                }

                std::reverse(solucion.begin( ), solucion.end( ));

                vasos ant = { v, 0, 0 }, act, sol;
                for (int i = 0; i < d; ++i, std::swap(ant, act)) {
                    act = solucion[i];
                    for (int j = 0; j < 3; ++j) {
                        if (ant[j] != act[j]) {
                            sol[(ant[j] > act[j] ? 0 : 1)] = j;
                            sol[2] = std::abs(ant[j] - act[j]);
                        }
                    }
                    std::printf("%d %d %d\n", sol[0], sol[1], sol[2]);
                }

                return 0;
            }

            for (int k = 0; k < 3; ++k) {
                for (int it : pos) {
                    int tope[2] = { (k + 1) % 3, (k + 2) % 3 };
                    for (int q = 0; q < 2; ++q) {
                        vasos temp = actual.first;
                        int x = it - temp[tope[q]];
                        if (x >= 0 && x <= v - temp[tope[q]] && temp[k] >= x) {
                            temp[k] -= x;
                            temp[tope[q]] += x;
                            auto itr = memo.insert(temp);
                            if (itr.second) {
                                cola.push_back({ temp, ini }), ++fin;
                            }
                        }
                    }
                }
            }
        }
    }
    std::printf("-1\n");
}