#include <bits/stdc++.h>
#define _GLIBCXX_DEBUG
using namespace std;
using ll = long long;
using vec = vector<ll>;
using vect = vector<double>;
using Graph = vector<vector<ll>>;
#define loop(i, n) for (ll i = 0; i < n; i++)
#define Loop(i, m, n) for (ll i = m; i < n; i++)
#define pool(i, n) for (ll i = n; i >= 0; i--)
#define Pool(i, m, n) for (ll i = n; i >= m; i--)
#define mod 1000000007ll
#define setbit bitset<8>
#define flagcount __builtin_popcount
#define flag(x) (1 << x)
#define flagadd(bit, x) bit |= flag(x)
#define flagpop(bit, x) bit &= ~flag(x)
#define flagon(bit, i) bit &flag(i)
#define flagoff(bit, i) !(bit & (1 << i))
#define all(v) v.begin(), v.end()
#define low2way(v, x) lower_bound(all(v), x)
#define high2way(v, x) upper_bound(all(v), x)
#define count2way(v, x) high2way(v, x) - low2way(v, x)
#define lower(v, x) low2way(v, x) - v.begin()       //1番左が0、もし見つから無いならｎを出力
#define higher(v, x) high2way(v, x) - v.begin() - 1 //1番左が0、もし見つからないならn-1を出力（注意）
#define putout(a) cout << a << endl
#define putout2(a, b) \
    putout(a);        \
    putout(b)
#define putout3(a, b, c) \
    putout(a);           \
    putout(b);           \
    putout(c)
#define putout4(a, b, c, d) \
    putout(a);              \
    putout(b);              \
    putout(c);              \
    putout(d)
#define putout5(a, b, c, d, e) \
    putout(a);                 \
    putout(b);                 \
    putout(c);                 \
    putout(d);                 \
    putout(e)
#define Gput(a, b) G[a].push_back(b)
#define cin1(a) cin >> a
#define cin2(a, b) cin >> a >> b
#define cin3(a, b, c) cin >> a >> b >> c
#define cin4(a, b, c, d) cin >> a >> b >> c >> d
#define cin5(a, b, c, d, e) cin >> a >> b >> c >> d >> e
#define Sum(v) accumulate(all(v), 0ll)
#define gcd(x, y) __gcd(x, y)
ll ctoi(char c)
{
    if (c >= '0' && c <= '9')
    {
        return c - '0';
    }
    return 0;
}
template <typename T>
T lcm(T x, T y)
{
    T z = gcd(x, y);
    return x * y / z;
}
template <typename T>
bool primejudge(T n)
{
    if (n < 2)
        return false;
    else if (n == 2)
        return true;
    else if (n % 2 == 0)
        return false;
    double sqrtn = sqrt(n);
    for (T i = 3; i < sqrtn + 1; i++)
    {
        if (n % i == 0)
        {
            return false;
        }
        i++;
    }
    return true;
}
template <typename T>
T modinv(T a, T m)
{
    T b = m, u = 1, v = 0;
    while (b)
    {
        T t = a / b;
        a -= t * b;
        swap(a, b);
        u -= t * v;
        swap(u, v);
    }
    u %= m;
    if (u < 0)
        u += m;
    return u;
}
//場合によって使い分ける
//const ll dx[4]={1,0,-1,0};
//const ll dy[4]={0,1,0,-1};
const ll dx[8] = {1, 1, 0, -1, -1, -1, 0, 1};
const ll dy[8] = {0, 1, 1, 1, 0, -1, -1, -1};
//多次元配列の宣言法
//vector<vector<ll>> field(h, vector<ll>(w));
template <class T>
inline void chmax(T &a, T b)
{
    if (a < b)
        a = b;
}
template <class T>
inline void chmin(T &a, T b)
{
    if (a > b)
        a = b;
}
/*
ライブラリをここに置いてコメントを削除
*/
template <typename flow_t, typename cost_t>
struct PrimalDual
{
    const cost_t INF;

    struct edge
    {
        int to;
        flow_t cap;
        cost_t cost;
        int rev;
        bool isrev;
    };
    vector<vector<edge>> graph;
    vector<cost_t> potential, min_cost;
    vector<int> prevv, preve;

    PrimalDual(int V) : graph(V), INF(numeric_limits<cost_t>::max()) {}

    void add_edge(int from, int to, flow_t cap, cost_t cost)
    {
        graph[from].emplace_back((edge){to, cap, cost, (int)graph[to].size(), false});
        graph[to].emplace_back((edge){from, 0, -cost, (int)graph[from].size() - 1, true});
    }

    cost_t min_cost_flow(int s, int t, flow_t f)
    {
        int V = (int)graph.size();
        cost_t ret = 0;
        using Pi = pair<cost_t, int>;
        priority_queue<Pi, vector<Pi>, greater<Pi>> que;
        potential.assign(V, 0);
        preve.assign(V, -1);
        prevv.assign(V, -1);

        while (f > 0)
        {
            min_cost.assign(V, INF);
            que.emplace(0, s);
            min_cost[s] = 0;
            while (!que.empty())
            {
                Pi p = que.top();
                que.pop();
                if (min_cost[p.second] < p.first)
                    continue;
                for (int i = 0; i < graph[p.second].size(); i++)
                {
                    edge &e = graph[p.second][i];
                    cost_t nextCost = min_cost[p.second] + e.cost + potential[p.second] - potential[e.to];
                    if (e.cap > 0 && min_cost[e.to] > nextCost)
                    {
                        min_cost[e.to] = nextCost;
                        prevv[e.to] = p.second, preve[e.to] = i;
                        que.emplace(min_cost[e.to], e.to);
                    }
                }
            }
            if (min_cost[t] == INF)
                return -1;
            for (int v = 0; v < V; v++)
                potential[v] += min_cost[v];
            flow_t addflow = f;
            for (int v = t; v != s; v = prevv[v])
            {
                addflow = min(addflow, graph[prevv[v]][preve[v]].cap);
            }
            f -= addflow;
            ret += addflow * potential[t];
            for (int v = t; v != s; v = prevv[v])
            {
                edge &e = graph[prevv[v]][preve[v]];
                e.cap -= addflow;
                graph[v][e.rev].cap += addflow;
            }
        }
        return ret;
    }

    void output()
    {
        for (int i = 0; i < graph.size(); i++)
        {
            for (auto &e : graph[i])
            {
                if (e.isrev)
                    continue;
                auto &rev_e = graph[e.to][e.rev];
                cout << i << "->" << e.to << " (flow: " << rev_e.cap << "/" << rev_e.cap + e.cap << ")" << endl;
            }
        }
    }
};
/*
*うしさんのライブラリ*
PrimalDual<ll,ll> G(V);等で宣言
G.add_edge(from,to,cap,cost):頂点fromから頂点toまで容量cap,コストcostの辺を張る
G.min_cost_flow(s,t,f):頂点sから頂点tへ流量fの最小費用流を流す
　　　　　　　　　　　　　流せた場合そのコストを、流せない場合-1を返す
*/
int main()
{
    cout << fixed << setprecision(30);
    ll V,E,F;
    cin>>V>>E>>F;
    PrimalDual<ll,ll> G(V);
    loop(i,E){
        ll a,b,c,d;
        cin>>a>>b>>c>>d;
        G.add_edge(a,b,c,d);
    }
    putout(G.min_cost_flow(0,V-1,F));
    return 0;
}


Measured memory_bytes: 3272