//#pragma GCC optimize("Ofast")
//#pragma GCC target("avx")
//#undef LOCAL


#include <algorithm>
#include <cassert>
#include <vector>

namespace atcoder {

struct dsu {
  public:
    dsu() : _n(0) {}
    dsu(int n) : _n(n), parent_or_size(n, -1) {}

    int merge(int a, int b) {
        assert(0 <= a && a < _n);
        assert(0 <= b && b < _n);
        int x = leader(a), y = leader(b);
        if (x == y) return x;
        if (-parent_or_size[x] < -parent_or_size[y]) std::swap(x, y);
        parent_or_size[x] += parent_or_size[y];
        parent_or_size[y] = x;
        return x;
    }

    bool same(int a, int b) {
        assert(0 <= a && a < _n);
        assert(0 <= b && b < _n);
        return leader(a) == leader(b);
    }

    int leader(int a) {
        assert(0 <= a && a < _n);
        if (parent_or_size[a] < 0) return a;
        return parent_or_size[a] = leader(parent_or_size[a]);
    }

    int size(int a) {
        assert(0 <= a && a < _n);
        return -parent_or_size[leader(a)];
    }

    std::vector<std::vector<int>> groups() {
        std::vector<int> leader_buf(_n), group_size(_n);
        for (int i = 0; i < _n; i++) {
            leader_buf[i] = leader(i);
            group_size[leader_buf[i]]++;
        }
        std::vector<std::vector<int>> result(_n);
        for (int i = 0; i < _n; i++) {
            result[i].reserve(group_size[i]);
        }
        for (int i = 0; i < _n; i++) {
            result[leader_buf[i]].push_back(i);
        }
        result.erase(
            std::remove_if(result.begin(), result.end(),
                           [&](const std::vector<int>& v) { return v.empty(); }),
            result.end());
        return result;
    }

  private:
    int _n;
    std::vector<int> parent_or_size;
};

}  // namespace atcoder


#include <algorithm>
#include <cassert>
#include <limits>
#include <queue>
#include <vector>


#include <vector>

namespace atcoder {

namespace internal {

template <class T> struct simple_queue {
    std::vector<T> payload;
    int pos = 0;
    void reserve(int n) { payload.reserve(n); }
    int size() const { return int(payload.size()) - pos; }
    bool empty() const { return pos == int(payload.size()); }
    void push(const T& t) { payload.push_back(t); }
    T& front() { return payload[pos]; }
    void clear() {
        payload.clear();
        pos = 0;
    }
    void pop() { pos++; }
};

}  // namespace internal

}  // namespace atcoder


namespace atcoder {

template <class Cap> struct mf_graph {
  public:
    mf_graph() : _n(0) {}
    mf_graph(int n) : _n(n), g(n) {}

    int add_edge(int from, int to, Cap cap) {
        assert(0 <= from && from < _n);
        assert(0 <= to && to < _n);
        assert(0 <= cap);
        int m = int(pos.size());
        pos.push_back({from, int(g[from].size())});
        int from_id = int(g[from].size());
        int to_id = int(g[to].size());
        if (from == to) to_id++;
        g[from].push_back(_edge{to, to_id, cap});
        g[to].push_back(_edge{from, from_id, 0});
        return m;
    }

    struct edge {
        int from, to;
        Cap cap, flow;
    };

    edge get_edge(int i) {
        int m = int(pos.size());
        assert(0 <= i && i < m);
        auto _e = g[pos[i].first][pos[i].second];
        auto _re = g[_e.to][_e.rev];
        return edge{pos[i].first, _e.to, _e.cap + _re.cap, _re.cap};
    }
    std::vector<edge> edges() {
        int m = int(pos.size());
        std::vector<edge> result;
        for (int i = 0; i < m; i++) {
            result.push_back(get_edge(i));
        }
        return result;
    }
    void change_edge(int i, Cap new_cap, Cap new_flow) {
        int m = int(pos.size());
        assert(0 <= i && i < m);
        assert(0 <= new_flow && new_flow <= new_cap);
        auto& _e = g[pos[i].first][pos[i].second];
        auto& _re = g[_e.to][_e.rev];
        _e.cap = new_cap - new_flow;
        _re.cap = new_flow;
    }

    Cap flow(int s, int t) {
        return flow(s, t, std::numeric_limits<Cap>::max());
    }
    Cap flow(int s, int t, Cap flow_limit) {
        assert(0 <= s && s < _n);
        assert(0 <= t && t < _n);
        assert(s != t);

        std::vector<int> level(_n), iter(_n);
        internal::simple_queue<int> que;

        auto bfs = [&]() {
            std::fill(level.begin(), level.end(), -1);
            level[s] = 0;
            que.clear();
            que.push(s);
            while (!que.empty()) {
                int v = que.front();
                que.pop();
                for (auto e : g[v]) {
                    if (e.cap == 0 || level[e.to] >= 0) continue;
                    level[e.to] = level[v] + 1;
                    if (e.to == t) return;
                    que.push(e.to);
                }
            }
        };
        auto dfs = [&](auto self, int v, Cap up) {
            if (v == s) return up;
            Cap res = 0;
            int level_v = level[v];
            for (int& i = iter[v]; i < int(g[v].size()); i++) {
                _edge& e = g[v][i];
                if (level_v <= level[e.to] || g[e.to][e.rev].cap == 0) continue;
                Cap d =
                    self(self, e.to, std::min(up - res, g[e.to][e.rev].cap));
                if (d <= 0) continue;
                g[v][i].cap += d;
                g[e.to][e.rev].cap -= d;
                res += d;
                if (res == up) return res;
            }
            level[v] = _n;
            return res;
        };

        Cap flow = 0;
        while (flow < flow_limit) {
            bfs();
            if (level[t] == -1) break;
            std::fill(iter.begin(), iter.end(), 0);
            Cap f = dfs(dfs, t, flow_limit - flow);
            if (!f) break;
            flow += f;
        }
        return flow;
    }

    std::vector<bool> min_cut(int s) {
        std::vector<bool> visited(_n);
        internal::simple_queue<int> que;
        que.push(s);
        while (!que.empty()) {
            int p = que.front();
            que.pop();
            visited[p] = true;
            for (auto e : g[p]) {
                if (e.cap && !visited[e.to]) {
                    visited[e.to] = true;
                    que.push(e.to);
                }
            }
        }
        return visited;
    }

  private:
    int _n;
    struct _edge {
        int to, rev;
        Cap cap;
    };
    std::vector<std::pair<int, int>> pos;
    std::vector<std::vector<_edge>> g;
};

}  // namespace atcoder


#include <array>
#include <cassert>
#include <chrono>
#include <cstdint>
#include <type_traits>


namespace yosupo {

namespace internal {

int ceil_pow2(int n) {
    int x = 0;
    while ((1U << x) < (unsigned int)(n)) x++;
    return x;
}

}  // namespace internal

int bsf(unsigned int n) { return __builtin_ctz(n); }
int bsf(unsigned long n) { return __builtin_ctzl(n); }
int bsf(unsigned long long n) { return __builtin_ctzll(n); }

int bsr(unsigned int n) {
    return 8 * (int)sizeof(unsigned int) - 1 - __builtin_clz(n);
}
int bsr(unsigned long n) {
    return 8 * (int)sizeof(unsigned long) - 1 - __builtin_clzl(n);
}
int bsr(unsigned long long n) {
    return 8 * (int)sizeof(unsigned long long) - 1 - __builtin_clzll(n);
}

}  // namespace yosupo

namespace yosupo {

struct Xoshiro256StarStar {
  public:
    using result_type = uint64_t;
    Xoshiro256StarStar() : Xoshiro256StarStar(0) {}
    explicit Xoshiro256StarStar(uint64_t seed) {
        for (int i = 0; i < 4; i++) {
            uint64_t z = (seed += 0x9e3779b97f4a7c15);
            z = (z ^ (z >> 30)) * 0xbf58476d1ce4e5b9;
            z = (z ^ (z >> 27)) * 0x94d049bb133111eb;
            s[i] = z ^ (z >> 31);
        }
    }

    static constexpr result_type min() { return 0; }
    static constexpr result_type max() { return -1; }

    result_type operator()() {
        const uint64_t result_starstar = rotl(s[1] * 5, 7) * 9;

        const uint64_t t = s[1] << 17;

        s[2] ^= s[0];
        s[3] ^= s[1];
        s[1] ^= s[2];
        s[0] ^= s[3];

        s[2] ^= t;

        s[3] = rotl(s[3], 45);

        return result_starstar;
    }

  private:
    static uint64_t rotl(const uint64_t x, int k) {
        return (x << k) | (x >> (64 - k));
    }

    std::array<uint64_t, 4> s;
};

namespace internal {

template <class G> uint64_t uniform(uint64_t upper, G& gen) {
    static_assert(std::is_same<uint64_t, typename G::result_type>::value, "");
    static_assert(G::min() == 0, "");
    static_assert(G::max() == uint64_t(-1), "");
    if (!(upper & (upper + 1))) {
        return gen() & upper;
    }
    int log = bsr(upper);
    uint64_t mask = (log == 63) ? ~0ULL : (1ULL << (log + 1)) - 1;
    while (true) {
        uint64_t r = gen() & mask;
        if (r <= upper) return r;
    }
}

}  // namespace internal

Xoshiro256StarStar& global_gen() {
    static Xoshiro256StarStar gen(
        std::chrono::steady_clock::now().time_since_epoch().count());
    return gen;
}

template <class T, class G> T uniform(T lower, T upper, G& gen) {
    return T(lower + internal::uniform(uint64_t(upper) - uint64_t(lower), gen));
}
template <class T> T uniform(T lower, T upper) {
    return uniform(lower, upper, global_gen());
}

template <class G> bool uniform_bool(G& gen) {
    return internal::uniform(1, gen) == 1;
}
bool uniform_bool() { return uniform_bool(global_gen()); }

template <class T, class G>
std::pair<T, T> uniform_pair(T lower, T upper, G& gen) {
    assert(upper - lower >= 1);
    T a, b;
    do {
        a = uniform(lower, upper, gen);
        b = uniform(lower, upper, gen);
    } while (a == b);
    if (a > b) std::swap(a, b);
    return {a, b};
}
template <class T> std::pair<T, T> uniform_pair(T lower, T upper) {
    return uniform_pair(lower, upper, global_gen());
}

}  // namespace yosupo
using namespace atcoder;
#include <algorithm>
#include <array>
#include <bitset>
#include <cassert>
#include <complex>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <map>
#include <numeric>
#include <queue>
#include <set>
#include <string>
#include <unordered_map>
#include <unordered_set>
#include <vector>

using namespace std;

using uint = unsigned int;
using ll = long long;
using ull = unsigned long long;
constexpr ll TEN(int n) { return (n == 0) ? 1 : 10 * TEN(n - 1); }
template <class T> using V = vector<T>;
template <class T> using VV = V<V<T>>;

#ifdef LOCAL

ostream& operator<<(ostream& os, __int128_t x) {
    if (x < 0) {
        os << "-";
        x *= -1;
    }
    if (x == 0) {
        return os << "0";
    }
    string s;
    while (x) {
        s += char(x % 10 + '0');
        x /= 10;
    }
    reverse(s.begin(), s.end());
    return os << s;
}
ostream& operator<<(ostream& os, __uint128_t x) {
    if (x == 0) {
        return os << "0";
    }
    string s;
    while (x) {
        s += char(x % 10 + '0');
        x /= 10;
    }
    reverse(s.begin(), s.end());
    return os << s;
}

template <class T, class U>
ostream& operator<<(ostream& os, const pair<T, U>& p);
template <class T> ostream& operator<<(ostream& os, const V<T>& v);
template <class T> ostream& operator<<(ostream& os, const deque<T>& v);
template <class T, size_t N>
ostream& operator<<(ostream& os, const array<T, N>& a);
template <class T> ostream& operator<<(ostream& os, const set<T>& s);
template <class T, class U>
ostream& operator<<(ostream& os, const map<T, U>& m);

template <class T, class U>
ostream& operator<<(ostream& os, const pair<T, U>& p) {
    return os << "P(" << p.first << ", " << p.second << ")";
}

template <class T> ostream& operator<<(ostream& os, const V<T>& v) {
    os << "[";
    bool f = false;
    for (auto d : v) {
        if (f) os << ", ";
        f = true;
        os << d;
    }
    return os << "]";
}

template <class T> ostream& operator<<(ostream& os, const deque<T>& v) {
    os << "[";
    bool f = false;
    for (auto d : v) {
        if (f) os << ", ";
        f = true;
        os << d;
    }
    return os << "]";
}
template <class T, size_t N>
ostream& operator<<(ostream& os, const array<T, N>& a) {
    os << "[";
    bool f = false;
    for (auto d : a) {
        if (f) os << ", ";
        f = true;
        os << d;
    }
    return os << "]";
}

template <class T> ostream& operator<<(ostream& os, const set<T>& s) {
    os << "{";
    bool f = false;
    for (auto d : s) {
        if (f) os << ", ";
        f = true;
        os << d;
    }
    return os << "}";
}

template <class T, class U>
ostream& operator<<(ostream& os, const map<T, U>& s) {
    os << "{";
    bool f = false;
    for (auto p : s) {
        if (f) os << ", ";
        f = true;
        os << p.first << ": " << p.second;
    }
    return os << "}";
}

struct PrettyOS {
    ostream& os;
    bool first;

    template <class T> auto operator<<(T&& x) {
        if (!first) os << ", ";
        first = false;
        os << x;
        return *this;
    }
};
template <class... T> void dbg0(T&&... t) {
    (PrettyOS{cerr, true} << ... << t);
}
#define dbg(...)                                            \
    do {                                                    \
        cerr << __LINE__ << " : " << #__VA_ARGS__ << " = "; \
        dbg0(__VA_ARGS__);                                  \
        cerr << endl;                                       \
    } while (false);
#else
#define dbg(...)
#endif

#include <unistd.h>

struct Scanner {
    int fd = -1;
    char line[(1 << 15) + 1];
    size_t st = 0, ed = 0;
    void reread() {
        memmove(line, line + st, ed - st);
        ed -= st;
        st = 0;
        ed += ::read(fd, line + ed, (1 << 15) - ed);
        line[ed] = '\0';
    }
    bool succ() {
        while (true) {
            if (st == ed) {
                reread();
                if (st == ed) return false;
            }
            while (st != ed && isspace(line[st])) st++;
            if (st != ed) break;
        }
        if (ed - st <= 50) {
            bool sep = false;
            for (size_t i = st; i < ed; i++) {
                if (isspace(line[i])) {
                    sep = true;
                    break;
                }
            }
            if (!sep) reread();
        }
        return true;
    }
    template <class T, enable_if_t<is_same<T, string>::value, int> = 0>
    bool read_single(T& ref) {
        if (!succ()) return false;
        while (true) {
            size_t sz = 0;
            while (st + sz < ed && !isspace(line[st + sz])) sz++;
            ref.append(line + st, sz);
            st += sz;
            if (!sz || st != ed) break;
            reread();            
        }
        return true;
    }
    template <class T, enable_if_t<is_integral<T>::value>* = nullptr>
    bool read_single(T& ref) {
        if (!succ()) return false;
        bool neg = false;
        if (line[st] == '-') {
            neg = true;
            st++;
        }
        ref = T(0);
        while (isdigit(line[st])) {
            ref = 10 * ref + (line[st++] & 0xf);
        }
        if (neg) ref = -ref;
        return true;
    }
    template <class T> bool read_single(V<T>& ref) {
        for (auto& d : ref) {
            if (!read_single(d)) return false;
        }
        return true;
    }
    void read() {}
    template <class H, class... T> void read(H& h, T&... t) {
        bool f = read_single(h);
        assert(f);
        read(t...);
    }
    int read_unsafe() { return 0; }
    template <class H, class... T> int read_unsafe(H& h, T&... t) {        
        bool f = read_single(h);
        if (!f) return 0;
        return 1 + read_unsafe(t...);
    }
    Scanner(FILE* fp) : fd(fileno(fp)) {}
};

struct Printer {
  public:
    template <bool F = false> void write() {}
    template <bool F = false, class H, class... T>
    void write(const H& h, const T&... t) {
        if (F) write_single(' ');
        write_single(h);
        write<true>(t...);
    }
    template <class... T> void writeln(const T&... t) {
        write(t...);
        write_single('\n');
    }

    Printer(FILE* _fp) : fp(_fp) {}
    ~Printer() { flush(); }

  private:
    static constexpr size_t SIZE = 1 << 15;
    FILE* fp;
    char line[SIZE], small[50];
    size_t pos = 0;
    void flush() {
        fwrite(line, 1, pos, fp);
        pos = 0;
    }
    void write_single(const char& val) {
        if (pos == SIZE) flush();
        line[pos++] = val;
    }
    template <class T, enable_if_t<is_integral<T>::value>* = nullptr>
    void write_single(T val) {
        if (pos > (1 << 15) - 50) flush();        
        if (val == 0) {
            write_single('0');
            return;
        }
        if (val < 0) {
            write_single('-');
            val = -val;  // todo min
        }
        size_t len = 0;
        while (val) {
            small[len++] = char(0x30 | (val % 10));
            val /= 10;
        }
        for (size_t i = 0; i < len; i++) {
            line[pos + i] = small[len - 1 - i];
        }
        pos += len;
    }
    void write_single(__int128 val) {
        if (pos > (1 << 15) - 50) flush();
        if (val == 0) {
            write_single('0');
            return;
        }
        if (val < 0) {
            write_single('-');
            val = -val;  // todo min
        }
        size_t len = 0;
        while (val) {
            small[len++] = char(0x30 | (val % 10));
            val /= 10;
        }
        for (size_t i = 0; i < len; i++) {
            line[pos + i] = small[len - 1 - i];
        }
        pos += len;
    }

    void write_single(const string& s) {
        for (char c : s) write_single(c);
    }
    void write_single(const char* s) {
        size_t len = strlen(s);
        for (size_t i = 0; i < len; i++) write_single(s[i]);
    }
    template <class T> void write_single(const V<T>& val) {
        auto n = val.size();
        for (size_t i = 0; i < n; i++) {
            if (i) write_single(' ');
            write_single(val[i]);
        }
    }
};
struct StopWatch {
    bool f = false;
    clock_t st;
    void start() {
        f = true;
        st = clock();
    }
    int msecs() {
        assert(f);
        return (clock()-st)*1000 / CLOCKS_PER_SEC;
    }
};

Scanner sc = Scanner(stdin);
Printer pr = Printer(stdout);

using cent = __int128;

struct E {
    int from, to, idx;
    cent c, d;
};

int main() {
    StopWatch sw;
    sw.start();
    int n, m; cent K;
    sc.read(n, m, K);

    V<E> edges;
    for (int i = 0; i < m; i++) {
        int u, v;
        cent c, d;
        sc.read(u, v, c, d);
        u--; v--;
        edges.push_back({u, v, i, c, d});
    }

    V<cent> costs;
    for (auto e : edges) {
        costs.push_back(e.c);
    }
    sort(costs.begin(), costs.end());
    costs.erase(unique(costs.begin(), costs.end()), costs.end());
    int k = int(costs.size());

    const cent INF = cent(TEN(18)) * cent(TEN(9));
    cent offset = 0;
    for (auto e : edges) {
        offset += e.c * e.d;
    }

    cent ans = 0;
    //for (int ph = 0; ph < 100; ph++) {
    while (sw.msecs() < 1800) {

        mf_graph<cent> g(m * k + 2);
        auto id = [&](int i, int j) {
            assert(0 <= i && i < m);
            assert(0 <= j && j < k);
            return i * k + j;
        };
        int sv = m * k, tv = sv + 1;
        for (auto e : edges) {        
            int i = e.idx;
            int bk = sv;
            for (int j = 0; j < k; j++) {
                int nw = id(i, j);
                g.add_edge(bk, nw, costs[j] * e.d);
                g.add_edge(nw, bk, INF);
                bk = nw;
            }
            g.add_edge(bk, tv, INF);
            int x =
                int(lower_bound(costs.begin(), costs.end(), e.c) - costs.begin());
            if (x) g.add_edge(sv, id(i, x - 1), INF);
        }

        shuffle(edges.begin(), edges.end(), yosupo::global_gen());
        //sort(edges.begin(), edges.end(), [&](E a, E b) { return a.c < b.c; });

        using P = pair<int, int>;
        VV<P> tr(n);
        V<int> path;
        auto dfs = [&](auto self, int s, int bk, int t) -> bool {
            if (s == t) return true;
            for (auto e : tr[s]) {
                if (e.first == bk) continue;
                if (self(self, e.first, s, t)) {
                    path.push_back(e.second);
                    return true;
                }
            }
            return false;
        };

        dsu d(n);
        for (auto e : edges) {
            int i = e.idx;
            if (d.same(e.from, e.to)) {
                path.clear();
                bool f = dfs(dfs, e.from, -1, e.to);
                assert(f);
                for (auto u: path) {
                    for (int j = 0; j < k; j++) {
                        int my = id(i, j);
                        int your = id(u, j);
                        g.add_edge(your, my, INF);
                    }
                }
                //
                continue;
            }
            // tree
            d.merge(e.from, e.to);
            tr[e.from].push_back({e.to, e.idx});
            tr[e.to].push_back({e.from, e.idx});
            int bk = sv;
            for (int j = 0; j < k; j++) {
                int nw = id(i, j);
                g.add_edge(bk, nw, TEN(18) - (costs[j] * K));
                bk = nw;
            }
        }

        cent z = g.flow(sv, tv);
        auto cut = g.min_cut(sv);
        cent cur_ans = offset + cent(n - 1) * TEN(18) - z;
        dbg(z, cur_ans);
        ans = max(ans, cur_ans);

/*        for (auto& e : edges) {
            int i = e.idx;
            int bk = sv;
            bool ok = false;
            for (int j = 0; j < k; j++) {
                int nw = id(i, j);
                if (cut[bk] && !cut[nw]) {
                    ok = true;
                    e.c = costs[j];
                    break;
                }
                bk = nw;
            }
            assert(ok);
        }*/
    }

/*    cent ans = offset;
    dsu d(n);
    for (auto& e : edges) {
        ans -= e.c * e.d;
        if (d.same(e.from, e.to)) continue;
        d.merge(e.from, e.to);
        ans += K * e.c;
    }

    dbg(offset, ans);*/
    pr.writeln(ans);
    return 0;
}