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

using vi = vector<int>; using vvi = vector<vi>; using vvvi = vector<vvi>;
using ll = long long int;
using vll = vector<ll>; using vvll = vector<vll>; using vvvll = vector<vvll>;
using vd = vector<double>; using vvd = vector<vd>; using vvvd = vector<vvd>;
using P = pair<int, int>;
using Pll = pair<ll, ll>;
using cdouble = complex<double>;

const double eps = 1e-7;
#define Loop(i, n) for(int i = 0; i < int(n); i++)
#define Loopll(i, n) for(ll i = 0; i < ll(n); i++)
#define Loop1(i, n) for(int i = 1; i <= int(n); i++)
#define Loopll1(i, n) for(ll i = 1; i <= ll(n); i++)
#define Loopr(i, n) for(int i = int(n) - 1; i >= 0; i--)
#define Looprll(i, n) for(ll i = ll(n) - 1; i >= 0; i--)
#define Loopr1(i, n) for(int i = int(n); i >= 1; i--)
#define Looprll1(i, n) for(ll i = ll(n); i >= 1; i--)
#define Foreach(buf, container) for(const auto &buf : container)
#define Foreachr(buf, container)  for(const auto &buf : reversed(container))
#define Loopdiag(i, j, h, w, sum) for(int i = ((sum) >= (h) ? (h) - 1 : (sum)), j = (sum) - i; i >= 0 && j < (w); i--, j++)
#define Loopdiagr(i, j, h, w, sum) for(int j = ((sum) >= (w) ? (w) - 1 : (sum)), i = (sum) - j; j >= 0 && i < (h); j--, i++)
#define Loopdiagsym(i, j, h, w, gap) for (int i = ((gap) >= 0 ? (gap) : 0), j = i - (gap); i < (h) && j < (w); i++, j++)
#define Loopdiagsymr(i, j, h, w, gap) for (int i = ((gap) > (h) - (w) - 1 ? (h) - 1 : (w) - 1 + (gap)), j = i - (gap); i >= 0 && j >= 0; i--, j--)
#define Loopitr(itr, container) for(auto itr = container.begin(); itr != container.end(); itr++)
#define quickio() std::ios::sync_with_stdio(false); std::cin.tie(0);
#define bitmanip(m,val) static_cast<bitset<(int)m>>(val)
#define Comp(type_t) bool operator<(const type_t &another) const
#define fst first
#define snd second
#define INF INFINITY
bool feq(double x, double y) { return abs(x - y) <= eps; }
bool inrange(ll x, ll t) { return x >= 0 && x < t; }
bool inrange(vll xs, ll t) { Foreach(x, xs) if (!(x >= 0 && x < t)) return false; return true; }
int ceillog2(ll x) { int m = int(log2(x)); return m + ((1LL << m) < x ? 1 : 0); }
int floorlog2(ll x) { int m = int(log2(x)); return m - ((1LL << m) > x ? 1 : 0); }
template<class T> T reversed(T container) { reverse(container.begin(), container.end()); return container; }
template<class T> void printv(const vector<T> &v) { for (const T &x : v) cout << x << " "; cout << endl; }
template<class T> void printmx(const vector<vector<T>> &mx) { for (const vector<T> &v : mx) printv(v); }
ll rndf(double x) { return (ll)(x + (x >= 0 ? 0.5 : -0.5)); }
ll floorsqrt(ll x) { ll m = (ll)sqrt((double)x); return m + (m*  m <= x ? 0 : -1); }
ll ceilsqrt(ll x) { ll m = (ll)sqrt((double)x); return m + (x <= m * m ? 0 : 1); }
ll rnddiv(ll a, ll b) { return (a / b + (a % b * 2 >= b ? 1 : 0)); }
ll ceildiv(ll a, ll b) { return (a / b + (a % b == 0 ? 0 : 1)); }
ll gcd(ll m, ll n) { if (n == 0) return m; else return gcd(n, m % n); }
ll lcm(ll m, ll n) { return ll(m) * ll(n) / gcd(m, n); }

//========================================================================//

class Mincostflow {
private:
	struct edge {
		int eid, from, to;
		ll cap, cost;
	};
	struct node {
		int id; ll d; int from_eid; vector<int> to_eids;
	};
	struct pq_t {
		int id; ll d;
		bool operator<(const pq_t & another) const {
			return d != another.d ? d > another.d : id > another.id;
		}
	};
	int dual_eid(int eid) {
		if (eid < m) return eid + m;
		else return eid - m;
	}
	vector<node> nodes;
	vector<edge> edges;
	int n, m;
	int source, sink;
	bool overflow;
public:
	Mincostflow(const vvi &lst, const vvll &cap, const vvll &cst, int s, int t) {
		n = lst.size();
		nodes.resize(n);
		Loop(i, n) nodes[i] = { i, LLONG_MAX, -1, {} };
		int eid = 0;
		Loop(i, n) {
			Loop(j, lst[i].size()) {
				nodes[i].to_eids.push_back(eid);
				edges.push_back({ eid, i, lst[i][j], cap[i][j], cst[i][j] });
				eid++;
			}
		}
		m = eid;
		Loop(i, n) {
			Loop(j, lst[i].size()) {
				nodes[lst[i][j]].to_eids.push_back(eid);
				edges.push_back({ eid, lst[i][j], i, 0, -cst[i][j] });
				eid++;
			}
		}
		source = s;
		sink = t;
		overflow = false;
	}
	bool add_flow(ll f) {
		if (overflow) return false;
		while (f > 0) {
			Loop(i, n) {
				nodes[i].d = LLONG_MAX;
				nodes[i].from_eid = -1;
			}
			// Bellmanford
			nodes[source].d = 0;
			Loop(k, n) {
				Loop(i, n) {
					int a = i;
					if (nodes[a].d == LLONG_MAX) continue;
					Foreach(eid, nodes[a].to_eids) {
						if (edges[eid].cap == 0) continue;
						int b = edges[eid].to;
						if (nodes[a].d + edges[eid].cost < nodes[b].d) {
							nodes[b].d = nodes[a].d + edges[eid].cost;
							nodes[b].from_eid = eid;
							if (k == n - 1) {
								return false;
							}
						}
					}
				}
			}
			if (nodes[sink].d == LLONG_MAX) return false;
			int a = sink;
			ll df = f;
			while (a != source) {
				df = min(df, edges[nodes[a].from_eid].cap);
				a = edges[nodes[a].from_eid].from;
			}
			a = sink;
			while (a != source) {
				edges[nodes[a].from_eid].cap -= df;
				edges[dual_eid(nodes[a].from_eid)].cap += df;
				a = edges[nodes[a].from_eid].from;
			}
			f -= df;
		}
		return true;
	}
	vll get_eid_flow() {
		vll ret(m, -1);
		if (overflow) return ret;
		Loop(i, m) {
			ret[i] = edges[i + m].cap;
		}
		return ret;
	}
	ll get_flow() {
		if (overflow) return -1;
		ll ret = 0;
		Foreach(eid, nodes[sink].to_eids) {
			if (eid >= m) ret += edges[eid].cap;
		}
		return ret;
	}
	ll get_cost() {
		if (overflow) return -1;
		ll ret = 0;
		Loop(i, m) {
			ret += edges[i].cost * edges[i + m].cap;
		}
		return ret;
	}
};

int main() {
	int n, m, f;
	cin >> n >> m >> f;
	vvi lst(n);
	vvll cap(n), cst(n);
	Loop(i, m) {
		int s, t, c, d; cin >> s >> t >> c >> d;
		lst[s].push_back(t);
		cap[s].push_back(c);
		cst[s].push_back(d);
	}
	Mincostflow mcf(lst, cap, cst, 0, n - 1);
	bool judge = mcf.add_flow(f);
	if (judge) cout << mcf.get_cost() << endl;
	else cout << -1 << endl;
	return 0;
}




Measured memory_bytes: 3332