#line 1 "combinatorial_opt/test/mcf_costscaling.yuki1615.test.cpp"
#define PROBLEM "https://yukicoder.me/problems/no/1615"
#line 2 "data_structure/light_forward_list.hpp"
#include <vector>

// CUT begin
// Simple forward_list for MLE-sensitive situations
// Verify: <http://judge.u-aizu.ac.jp/onlinejudge/description.jsp?id=ALDS1_14_D>
template <typename T> struct light_forward_list {
    static std::vector<unsigned> ptr;
    static std::vector<T> val;
    unsigned head;
    light_forward_list() : head(0) {}
    void push_front(T x) {
        ptr.push_back(head), val.push_back(x);
        head = ptr.size() - 1;
    }
    struct iterator {
        unsigned p;
        iterator operator++() { return {p = ptr[p]}; }
        T &operator*() { return val[p]; }
        bool operator!=(const iterator &rhs) { return p != rhs.p; }
    };
    iterator begin() { return {head}; }
    iterator end() { return {0}; }
};
template <typename T> std::vector<unsigned> light_forward_list<T>::ptr = {0};
template <typename T> std::vector<T> light_forward_list<T>::val = {T()};
#line 3 "combinatorial_opt/mcf_costscaling.hpp"
#include <cassert>
#include <queue>
#line 6 "combinatorial_opt/mcf_costscaling.hpp"

// Cost scaling
// https://people.orie.cornell.edu/dpw/orie633/
// Implementation idea: https://yukicoder.me/submissions/680169
template <class Cap, class Cost, int SCALING = 1, int SKIP_REFINE_DEPTH = 20> struct mcf_costscaling {
    mcf_costscaling() = default;
    mcf_costscaling(int n) : _n(n), to(n), b(n), p(n) {}

    int _n;
    std::vector<Cap> cap;
    std::vector<Cost> cost;
    std::vector<int> opposite;
    std::vector<light_forward_list<int>> to;
    std::vector<Cap> b;
    std::vector<Cost> p;

    void add_edge(int from_, int to_, Cap cap_, Cost cost_) {
        assert(0 <= from_ && from_ < _n);
        assert(0 <= to_ && to_ < _n);
        assert(0 <= cap_);
        cost_ *= (_n + 1);

        int e = int(cap.size());
        to[from_].push_front(e);
        cap.push_back(cap_);
        cost.push_back(cost_);
        opposite.push_back(to_);

        to[to_].push_front(e + 1);
        cap.push_back(0);
        cost.push_back(-cost_);
        opposite.push_back(from_);
    }
    void add_supply(int v, Cap supply) { b[v] += supply; }
    void add_demand(int v, Cap demand) { add_supply(v, -demand); }

    template <typename RetCost = Cost> RetCost solve() {
        Cost eps = 1;
        std::queue<int> q;
        for (const auto c : cost) {
            while (eps <= -c) eps <<= SCALING;
        }
        for (; eps >>= SCALING;) {
            auto no_negative_loop = [&]() -> bool {
                std::vector<Cost> dist = p;
                for (int iter = 0; iter < SKIP_REFINE_DEPTH; iter++) {
                    bool flg = false;
                    for (int e = 0; e < int(cap.size()); e++) {
                        if (!cap[e]) continue;
                        int i = opposite[e ^ 1], j = opposite[e];
                        if (dist[j] > dist[i] + cost[e] + eps) {
                            dist[j] = dist[i] + cost[e] + eps;
                            flg = true;
                        }
                    }
                    if (!flg) {
                        p = dist;
                        return true;
                    }
                }
                return false;
            };
            if (no_negative_loop()) continue;
            for (int e = 0; e < int(cap.size()); e += 2) {
                const int i = opposite[e ^ 1], j = opposite[e];
                const Cost cp_ij = cost[e] + p[i] - p[j];
                if (cap[e] and cp_ij < 0) {
                    b[i] -= cap[e], b[j] += cap[e], cap[e ^ 1] += cap[e], cap[e] = 0;
                } else if (cap[e ^ 1] and cp_ij > 0) {
                    b[i] += cap[e ^ 1], b[j] -= cap[e ^ 1], cap[e] += cap[e ^ 1], cap[e ^ 1] = 0;
                }
            }
            for (int i = 0; i < _n; i++) {
                if (b[i] > 0) q.push(i);
            }
            while (q.size()) {
                const int i = q.front();
                q.pop();
                for (auto e : to[i]) { // Push
                    if (!cap[e]) continue;
                    int j = opposite[e];
                    Cost cp_ij = cost[e] + p[i] - p[j];
                    if (cp_ij >= 0) continue;
                    Cap f = b[i] > cap[e] ? cap[e] : b[i];
                    if (b[j] <= 0 and b[j] + f > 0) q.push(j);
                    b[i] -= f, b[j] += f, cap[e] -= f, cap[e ^ 1] += f;
                    if (!b[i]) break;
                }

                if (b[i] > 0) { // Relabel
                    bool flg = false;
                    for (int e : to[i]) {
                        if (!cap[e]) continue;
                        Cost x = p[opposite[e]] - cost[e] - eps;
                        if (!flg or x > p[i]) flg = true, p[i] = x;
                    }
                    q.push(i);
                }
            }
        }
        RetCost ret = 0;
        for (int e = 0; e < int(cap.size()); e += 2) ret += RetCost(cost[e]) * cap[e ^ 1];
        return ret / (_n + 1);
    }
    std::vector<Cost> potential() {
        std::vector<Cost> ret = p;
        for (auto &x : ret) x /= (_n + 1);
        while (true) {
            bool flg = false;
            for (int i = 0; i < _n; i++) {
                for (auto e : to[i]) {
                    if (!cap[e]) continue;
                    int j = opposite[e];
                    auto y = ret[i] + cost[e] / (_n + 1);
                    if (ret[j] > y) ret[j] = y, flg = true;
                }
            }
            if (!flg) break;
        }
        return ret;
    }
    struct edge {
        int from, to;
        Cap cap, flow;
        Cost cost;
    };
    edge get_edge(int e) const {
        int m = cap.size() / 2;
        assert(e >= 0 and e < m);
        return {opposite[e * 2 + 1], opposite[e * 2], cap[e * 2] + cap[e * 2 + 1], cap[e * 2 + 1], cost[e * 2] / (_n + 1)};
    }
    std::vector<edge> edges() const {
        int m = cap.size() / 2;
        std::vector<edge> result(m);
        for (int i = 0; i < m; i++) result[i] = get_edge(i);
        return result;
    }
};
#line 3 "combinatorial_opt/test/mcf_costscaling.yuki1615.test.cpp"
#include <iostream>
using namespace std;

int main() {
    int N, M, K, L;
    cin >> N >> M >> K >> L;
    mcf_costscaling<int, long long, 2, 20> mcf(N + M + 2);
    for (int l = 0; l < L; l++) {
        int x, y, z;
        cin >> x >> y >> z;
        x--, y--;
        mcf.add_edge(x, y + N, 1, -(1LL << z));
    }
    const int gs = N + M, gt = gs + 1;
    for (int i = 0; i < N; i++) mcf.add_edge(gs, i, 1, 0);
    for (int j = 0; j < M; j++) mcf.add_edge(N + j, gt, 1, 0);
    mcf.add_edge(gt, gs, N + M, 0);
    cout << -mcf.solve() << '\n';
}