#include <bits/stdc++.h>
using namespace std;

// https://judge.yosupo.jp/submission/51957

struct linked_lists {
    int L, N;
    vector<int> next, prev;

    // L: lists are [0...L), N: integers are [0...N)
    explicit linked_lists(int L = 0, int N = 0) { assign(L, N); }

    int rep(int l) const { return l + N; }
    int head(int l) const { return next[rep(l)]; }
    int tail(int l) const { return prev[rep(l)]; }
    bool empty(int l) const { return next[rep(l)] == rep(l); }

    void init(int l, int n) { meet(rep(l), n, rep(l)); }
    void clear(int l) { next[rep(l)] = prev[rep(l)] = rep(l); }

    void push_front(int l, int n) { assert(l < L && n < N), meet(rep(l), n, head(l)); }
    void push_back(int l, int n) { assert(l < L && n < N), meet(tail(l), n, rep(l)); }
    void insert_before(int i, int n) { assert(i < N && n < N), meet(prev[i], n, i); }
    void insert_after(int i, int n) { assert(i < N && n < N), meet(i, n, next[i]); }
    void erase(int n) { assert(n < N), meet(prev[n], next[n]); }
    void pop_front(int l) { assert(l < L && !empty(l)), meet(rep(l), next[head(l)]); }
    void pop_back(int l) { assert(l < L && !empty(l)), meet(prev[tail(l)], rep(l)); }

    void splice_front(int l, int b) {
        if (l != b && !empty(b))
            meet(tail(b), head(l)), meet(rep(l), head(b)), clear(b);
    }
    void splice_back(int l, int b) {
        if (l != b && !empty(b))
            meet(tail(l), head(b)), meet(tail(b), rep(l)), clear(b);
    }

    void clear() {
        iota(begin(next) + N, end(next), N);
        iota(begin(prev) + N, end(prev), N);
    }
    void assign(int L, int N) {
        this->L = L, this->N = N;
        next.resize(N + L), prev.resize(N + L), clear();
    }

  private:
    inline void meet(int u, int v) { next[u] = v, prev[v] = u; }
    inline void meet(int u, int v, int w) { meet(u, v), meet(v, w); }
};

#define FOR_EACH_IN_LINKED_LIST(i, l, lists) \
    for (int z##i = l, i = lists.head(z##i); i != lists.rep(z##i); i = lists.next[i])

#define FOR_EACH_IN_LINKED_LIST_REVERSE(i, l, lists) \
    for (int z##i = l, i = lists.tail(z##i); i != lists.rep(z##i); i = lists.prev[i])

template <typename Flow = long, typename Cost = long, typename CostSum = Cost>
struct network_simplex {
    explicit network_simplex(int V) : V(V), node(V + 1) {}

    void add(int u, int v, Flow lower, Flow upper, Cost cost) {
        assert(0 <= u && u < V && 0 <= v && v < V);
        edge.push_back({{u, v}, lower, upper, cost}), E++;
    }

    void add_supply(int u, Flow supply) { node[u].supply += supply; }
    void add_demand(int u, Flow demand) { node[u].supply -= demand; }

    auto get_supply(int u) const { return node[u].supply; }
    auto get_potential(int u) const { return node[u].pi; }
    auto get_flow(int e) const { return edge[e].flow; }

    auto get_circulation_cost() const {
        CostSum sum = 0;
        for (int e = 0; e < E; e++) {
            sum += edge[e].flow * CostSum(edge[e].cost);
        }
        return sum;
    }

    auto mincost_circulation() {
        static constexpr bool INFEASIBLE = false, OPTIMAL = true;

        Flow sum_supply = 0;
        for (int u = 0; u < V; u++) {
            sum_supply += node[u].supply;
        }
        if (sum_supply != 0) {
            return INFEASIBLE;
        }
        for (int e = 0; e < E; e++) {
            if (edge[e].lower > edge[e].upper) {
                return INFEASIBLE;
            }
        }

        init();
        int in_arc = select_pivot_edge();
        while (in_arc != -1) {
            pivot(in_arc);
            in_arc = select_pivot_edge();
        }

        for (int e = 0; e < E; e++) {
            auto [u, v] = edge[e].node;
            edge[e].flow += edge[e].lower;
            edge[e].upper += edge[e].lower;
            node[u].supply += edge[e].lower;
            node[v].supply -= edge[e].lower;
        }
        for (int e = E; e < E + V; e++) {
            if (edge[e].flow != 0) {
                edge.resize(E);
                return INFEASIBLE;
            }
        }
        edge.resize(E);
        return OPTIMAL;
    }

  private:
    enum ArcState : int8_t { STATE_UPPER = -1, STATE_TREE = 0, STATE_LOWER = 1 };

    struct Node {
        int parent, pred;
        Flow supply;
        CostSum pi;
    };
    struct Edge {
        int node[2];
        Flow lower, upper;
        Cost cost;
        Flow flow = 0;
        ArcState state = STATE_LOWER;
    };
    int V, E = 0, next_arc = 0, block_size = 0;
    vector<Node> node;
    vector<Edge> edge;
    linked_lists children;
    vector<int> bfs; // scratchpad for pi bfs and upwards walk

    auto reduced_cost(int e) const {
        auto [u, v] = edge[e].node;
        return edge[e].cost + node[u].pi - node[v].pi;
    }
    void init() {
        Cost slack_cost = 0;

        for (int e = 0; e < E; e++) {
            auto [u, v] = edge[e].node;
            edge[e].flow = 0;
            edge[e].state = STATE_LOWER;
            edge[e].upper -= edge[e].lower;
            node[u].supply -= edge[e].lower;
            node[v].supply += edge[e].lower;
            slack_cost += edge[e].cost < 0 ? -edge[e].cost : edge[e].cost;
        }

        edge.resize(E + V);
        bfs.resize(V + 1);
        children.assign(V + 1, V + 1);
        next_arc = 0;

        // Remove non-zero lower bounds
        int root = V;
        node[root] = {-1, -1, 0, 0};

        for (int u = 0, e = E; u < V; u++, e++) {
            node[u].parent = root, node[u].pred = e;
            children.push_back(root, u);
            auto supply = node[u].supply;
            if (supply >= 0) {
                node[u].pi = -slack_cost;
                edge[e] = {{u, root}, 0, supply, slack_cost, supply, STATE_TREE};
            } else {
                node[u].pi = slack_cost;
                edge[e] = {{root, u}, 0, -supply, slack_cost, -supply, STATE_TREE};
            }
        }

        block_size = max(int(ceil(sqrt(V + 1))), min(10, V + 1));
    }

    int select_pivot_edge() { // lemon-like block search
        int in_arc = -1;
        int count = block_size, seen_edges = E + V;
        Cost minimum = 0;
        for (int e = next_arc; seen_edges-- > 0; e = e + 1 == E + V ? 0 : e + 1) {
            if (minimum > edge[e].state * reduced_cost(e)) {
                minimum = edge[e].state * reduced_cost(e);
                in_arc = e;
            }
            if (--count == 0 && minimum < 0) {
                next_arc = e + 1 == E + V ? 0 : e + 1;
                return in_arc;
            } else if (count == 0) {
                count = block_size;
            }
        }
        return in_arc;
    }

    void pivot(int in_arc) {
        // Find join node
        auto [u_in, v_in] = edge[in_arc].node;
        int a = u_in, b = v_in;
        while (a != b) {
            a = node[a].parent == -1 ? v_in : node[a].parent;
            b = node[b].parent == -1 ? u_in : node[b].parent;
        }
        int join = a;

        // we add flow to source->target
        int source = edge[in_arc].state == STATE_LOWER ? u_in : v_in;
        int target = edge[in_arc].state == STATE_LOWER ? v_in : u_in;

        enum OutArcSide { SAME_EDGE, FIRST_SIDE, SECOND_SIDE };
        Flow flow_delta = edge[in_arc].upper;
        OutArcSide side = SAME_EDGE;
        int u_out = -1;

        // Go up the cycle from source to the join node
        for (int u = source; u != join; u = node[u].parent) {
            int e = node[u].pred;
            bool edge_down = u == edge[e].node[1];
            Flow d = edge_down ? edge[e].upper - edge[e].flow : edge[e].flow;
            if (flow_delta > d) {
                flow_delta = d;
                u_out = u;
                side = FIRST_SIDE;
            }
        }

        // Go up the cycle from target to the join node
        for (int u = target; u != join; u = node[u].parent) {
            int e = node[u].pred;
            bool edge_up = u == edge[e].node[0];
            Flow d = edge_up ? edge[e].upper - edge[e].flow : edge[e].flow;
            if (flow_delta >= d) {
                flow_delta = d;
                u_out = u;
                side = SECOND_SIDE;
            }
        }

        // Put u_in on the same side as u_out
        u_in = side == FIRST_SIDE ? source : target;
        v_in = side == FIRST_SIDE ? target : source;

        // Augment along the cycle
        if (flow_delta) {
            auto delta = edge[in_arc].state * flow_delta;
            edge[in_arc].flow += delta;
            for (int u = edge[in_arc].node[0]; u != join; u = node[u].parent) {
                int e = node[u].pred;
                edge[e].flow += (u == edge[e].node[0] ? -1 : +1) * delta;
            }
            for (int u = edge[in_arc].node[1]; u != join; u = node[u].parent) {
                int e = node[u].pred;
                edge[e].flow += (u == edge[e].node[0] ? +1 : -1) * delta;
            }
        }

        if (side == SAME_EDGE) {
            edge[in_arc].state = ArcState(-edge[in_arc].state);
            return;
        }

        int out_arc = node[u_out].pred;
        edge[in_arc].state = STATE_TREE;
        edge[out_arc].state = edge[out_arc].flow ? STATE_UPPER : STATE_LOWER;

        int i = 0, S = 0;
        for (int u = u_in; u != u_out; u = node[u].parent) {
            bfs[S++] = u;
        }
        for (i = S - 1; i >= 0; i--) {
            int u = bfs[i], p = node[u].parent;
            children.erase(p);
            children.push_back(u, p);
            node[p].parent = u;
            node[p].pred = node[u].pred;
        }
        children.erase(u_in);
        children.push_back(v_in, u_in);
        node[u_in].parent = v_in;
        node[u_in].pred = in_arc;

        CostSum current_pi = reduced_cost(in_arc);
        CostSum pi_delta = (u_in == edge[in_arc].node[0] ? -1 : +1) * current_pi;
        assert(pi_delta != 0);

        bfs[0] = u_in;
        for (i = 0, S = 1; i < S; i++) {
            int u = bfs[i];
            node[u].pi += pi_delta;
            FOR_EACH_IN_LINKED_LIST (v, u, children) { bfs[S++] = v; }
        }
    }
};

using ll = long long;
using ld = long double;
using ull = unsigned long long;
using uint = unsigned;
using pcc = pair<char, char>;
using pii = pair<int, int>;
using pll = pair<ll, ll>;
using pdd = pair<ld, ld>;
using tuplis = array<ll, 3>;
template<class T> using pq = priority_queue<T, vector<T>, greater<T>>;
const ll LINF=0x1fffffffffffffff;
const ll MINF=0x7fffffffffff;
const int INF=0x3fffffff;
const int MOD=1000000007;
const int MODD=998244353;
const ld DINF=numeric_limits<ld>::infinity();
const ld EPS=1e-9;
const ld PI=3.1415926535897932;
const ll dx[] = {0, 1, 0, -1, 1, -1, 1, -1};
const ll dy[] = {1, 0, -1, 0, 1, 1, -1, -1};
#define overload4(_1,_2,_3,_4,name,...) name
#define overload3(_1,_2,_3,name,...) name
#define rep1(n) for(ll i=0;i<n;++i)
#define rep2(i,n) for(ll i=0;i<n;++i)
#define rep3(i,a,b) for(ll i=a;i<b;++i)
#define rep4(i,a,b,c) for(ll i=a;i<b;i+=c)
#define rep(...) overload4(__VA_ARGS__,rep4,rep3,rep2,rep1)(__VA_ARGS__)
#define rrep1(n) for(ll i=n;i--;)
#define rrep2(i,n) for(ll i=n;i--;)
#define rrep3(i,a,b) for(ll i=b;i-->(a);)
#define rrep4(i,a,b,c) for(ll i=(a)+((b)-(a)-1)/(c)*(c);i>=(a);i-=c)
#define rrep(...) overload4(__VA_ARGS__,rrep4,rrep3,rrep2,rrep1)(__VA_ARGS__)
#define each1(i,a) for(auto&&i:a)
#define each2(x,y,a) for(auto&&[x,y]:a)
#define each3(x,y,z,a) for(auto&&[x,y,z]:a)
#define each(...) overload4(__VA_ARGS__,each3,each2,each1)(__VA_ARGS__)
#define all1(i) begin(i),end(i)
#define all2(i,a) begin(i),begin(i)+a
#define all3(i,a,b) begin(i)+a,begin(i)+b
#define all(...) overload3(__VA_ARGS__,all3,all2,all1)(__VA_ARGS__)
#define rall1(i) (i).rbegin(),(i).rend()
#define rall2(i,k) (i).rbegin(),(i).rbegin()+k
#define rall3(i,a,b) (i).rbegin()+a,(i).rbegin()+b
#define rall(...) overload3(__VA_ARGS__,rall3,rall2,rall1)(__VA_ARGS__)
#define sum(...) accumulate(all(__VA_ARGS__),0LL)
#define dsum(...) accumulate(all(__VA_ARGS__),0.0L)
#define Msum(...) accumulate(all(__VA_ARGS__),0_M)
#define elif else if
#define unless(a) if(!(a))
#define INT(...) int __VA_ARGS__;in(__VA_ARGS__)
#define LL(...) ll __VA_ARGS__;in(__VA_ARGS__)
#define ULL(...) ull __VA_ARGS__;in(__VA_ARGS__)
#define STR(...) string __VA_ARGS__;in(__VA_ARGS__)
#define CHR(...) char __VA_ARGS__;in(__VA_ARGS__)
#define DBL(...) double __VA_ARGS__;in(__VA_ARGS__)
#define LD(...) ld __VA_ARGS__;in(__VA_ARGS__)
#define Sort(a) sort(all(a))
#define Rev(a) reverse(all(a))
#define Uniq(a) sort(all(a));a.erase(unique(all(a)),end(a))
#define vec(type,name,...) vector<type>name(__VA_ARGS__)
#define VEC(type,name,size) vector<type>name(size);in(name)
#define vv(type,name,h,...) vector<vector<type>>name(h,vector<type>(__VA_ARGS__))
#define VV(type,name,h,w) vector<vector<type>>name(h,vector<type>(w));in(name)
#define vvv(type,name,h,w,...) vector<vector<vector<type>>>name(h,vector<vector<type>>(w,vector<type>(__VA_ARGS__)))
template<class T> auto min(const T& a){ return *min_element(all(a)); }
template<class T> auto max(const T& a){ return *max_element(all(a)); }
inline ll popcnt(ull a){ return __builtin_popcountll(a); }
ll intpow(ll a, ll b){ ll ans = 1; while(b){ if(b & 1) ans *= a; a *= a; b /= 2; } return ans; }
ll modpow(ll a, ll b, ll p){ ll ans = 1; while(b){ if(b & 1) (ans *= a) %= p; (a *= a) %= p; b /= 2; } return ans; }
template<class T> bool chmin(T& a, const T& b){ if(a > b){ a = b; return 1; } return 0; }
template<class T> bool chmax(T& a, const T& b){ if(a < b){ a = b; return 1; } return 0; }
template<class T, class U> bool chmin(T& a, const U& b){ if(a > T(b)){ a = b; return 1; } return 0; }
template<class T, class U> bool chmax(T& a, const U& b){ if(a < T(b)){ a = b; return 1; } return 0; }
vector<ll> iota(ll n, ll begin = 0){ vector<ll> a(n); iota(a.begin(), a.end(), begin); return a; }
vector<pll> factor(ull x){ vector<pll> ans; for(ull i = 2; i * i <= x; i++) if(x % i == 0){ ans.push_back({i, 1}); while((x /= i) % i == 0) ans.back().second++; } if(x != 1) ans.push_back({x, 1}); return ans; }
map<ll,ll> factor_map(ull x){ map<ll,ll> ans; for(ull i = 2; i * i <= x; i++) if(x % i == 0){ ans[i] = 1; while((x /= i) % i == 0) ans[i]++; } if(x != 1) ans[x] = 1; return ans; }
vector<ll> divisor(ull x){ vector<ll> ans; for(ull i = 1; i * i <= x; i++) if(x % i == 0) ans.push_back(i); rrep(ans.size() - (ans.back() * ans.back() == x)) ans.push_back(x / ans[i]); return ans; }
template<class T> unordered_map<T, ll> press(vector<T> a){ Uniq(a); unordered_map<T, ll> ans; rep(a.size()) ans[a[i]] = i; return ans; }
template<class T> map<T, ll> press_map(vector<T> a){ Uniq(a); map<T, ll> ans; rep(a.size()) ans[a[i]] = i; return ans; }
int scan(){ return getchar(); }
void scan(int& a){ scanf("%d", &a); }
void scan(unsigned& a){ scanf("%u", &a); }
void scan(long& a){ scanf("%ld", &a); }
void scan(long long& a){ scanf("%lld", &a); }
void scan(unsigned long long& a){ scanf("%llu", &a); }
void scan(char& a){ do{ a = getchar(); }while(a == ' ' || a == '\n'); }
void scan(float& a){ scanf("%f", &a); }
void scan(double& a){ scanf("%lf", &a); }
void scan(long double& a){ scanf("%Lf", &a); }
void scan(vector<bool>& a){ for(unsigned i = 0; i < a.size(); i++){ int b; scan(b); a[i] = b; } }
void scan(char a[]){ scanf("%s", a); }
void scan(string& a){ cin >> a; }
template<class T> void scan(vector<T>&);
template<class T, size_t size> void scan(array<T, size>&);
template<class T, class L> void scan(pair<T, L>&);
template<class T, size_t size> void scan(T(&)[size]);
template<class T> void scan(vector<T>& a){ for(auto&& i : a) scan(i); }
template<class T> void scan(deque<T>& a){ for(auto&& i : a) scan(i); }
template<class T, size_t size> void scan(array<T, size>& a){ for(auto&& i : a) scan(i); }
template<class T, class L> void scan(pair<T, L>& p){ scan(p.first); scan(p.second); }
template<class T, size_t size> void scan(T (&a)[size]){ for(auto&& i : a) scan(i); }
template<class T> void scan(T& a){ cin >> a; }
void in(){}
template <class... T> void in(T&... a){ (void)initializer_list<int>{ (scan(a), 0)... }; }
void print(){ putchar(' '); }
void print(bool a){ printf("%d", a); }
void print(int a){ printf("%d", a); }
void print(unsigned a){ printf("%u", a); }
void print(long a){ printf("%ld", a); }
void print(long long a){ printf("%lld", a); }
void print(unsigned long long a){ printf("%llu", a); }
void print(char a){ printf("%c", a); }
void print(char a[]){ printf("%s", a); }
void print(const char a[]){ printf("%s", a); }
void print(float a){ printf("%.15f", a); }
void print(double a){ printf("%.15f", a); }
void print(long double a){ printf("%.15Lf", a); }
void print(const string& a){ for(auto&& i : a) print(i); }
template<class T> void print(const complex<T>& a){ if(a.real() >= 0) print('+'); print(a.real()); if(a.imag() >= 0) print('+'); print(a.imag()); print('i'); }
template<class T> void print(const vector<T>&);
template<class T, size_t size> void print(const array<T, size>&);
template<class T, class L> void print(const pair<T, L>& p);
template<class T, size_t size> void print(const T (&)[size]);
template<class T> void print(const vector<T>& a){ if(a.empty()) return; print(a[0]); for(auto i = a.begin(); ++i != a.end(); ){ putchar(' '); print(*i); } }
template<class T> void print(const deque<T>& a){ if(a.empty()) return; print(a[0]); for(auto i = a.begin(); ++i != a.end(); ){ putchar(' '); print(*i); } }
template<class T, size_t size> void print(const array<T, size>& a){ print(a[0]); for(auto i = a.begin(); ++i != a.end(); ){ putchar(' '); print(*i); } }
template<class T, class L> void print(const pair<T, L>& p){ print(p.first); putchar(' '); print(p.second); }
template<class T, size_t size> void print(const T (&a)[size]){ print(a[0]); for(auto i = a; ++i != end(a); ){ putchar(' '); print(*i); } }
template<class T> void print(const T& a){ cout << a; }
int out(){ putchar('\n'); return 0; }
template<class T> int out(const T& t){ print(t); putchar('\n'); return 0; }
template<class Head, class... Tail> int out(const Head& head, const Tail&... tail){ print(head); putchar(' '); out(tail...); return 0; }
#ifdef DEBUG
inline ll __lg(ull x){ return 63 - __builtin_clzll(x); }
#define debug(...) { print(#__VA_ARGS__); print(":"); out(__VA_ARGS__); }
#else
#define debug(...) void(0)
#endif
int first(bool i = true){ return out(i?"first":"second"); }
int First(bool i = true){ return out(i?"First":"Second"); }
int yes(bool i = true){ return out(i?"yes":"no"); }
int Yes(bool i = true){ return out(i?"Yes":"No"); }
int No(){ return out("No"); }
int YES(bool i = true){ return out(i?"YES":"NO"); }
int NO(){ return out("NO"); }
int Yay(bool i = true){ return out(i?"Yay!":":("); }
int possible(bool i = true){ return out(i?"possible":"impossible"); }
int Possible(bool i = true){ return out(i?"Possible":"Impossible"); }
int POSSIBLE(bool i = true){ return out(i?"POSSIBLE":"IMPOSSIBLE"); }
void Case(ll i){ printf("Case #%lld: ", i); }



int main(){
    LL(n,m,k,l);
    const ll S=n+m;
    network_simplex<ll,ll,ll>g(S+1);
    rep(n)g.add_supply(i,1);
    rep(i,n,S)g.add_supply(i,-1);
    g.add_supply(S,m-n);
    rep(n)g.add(i,S,0,1,0);
    rep(i,n,S)g.add(S,i,0,1,0);
    rep(l){
        LL(x,y,z);
        x--; y+=n-1;
        g.add(x,y,0,1,-1LL<<z);
    }
    g.mincost_circulation();
    out(-g.get_circulation_cost());
}