// need
#include <iostream>
#include <algorithm>

// data structure
#include <bitset>
#include <map>
#include <queue>
#include <set>
#include <stack>
#include <string>
#include <utility>
#include <vector>
//#include <array>
#include <unordered_map>
//#include <complex>
//#include <deque>
#include <valarray>

// stream
//#include <istream>
#include <sstream>
//#include <ostream>
//#include <fstream>

// etc
#include <cassert>
#include <cmath>
#include <functional>
#include <iomanip>
#include <chrono>
#include <random>
#include <numeric>

//namespace std {
//	template < typename T > std::string to_string(const T& n) {
//		std::ostringstream stm;
//		stm << n;
//		return stm.str();
//	}
//	int stoi(std::string s, int tmp = 10) {
//		std::istringstream stm(s);
//		int res;
//		stm >> res;
//		return res;
//	}
//}

// input
#define INIT std::ios::sync_with_stdio(false);std::cin.tie(0);
#define VAR(type, ...)type __VA_ARGS__;MACRO_VAR_Scan(__VA_ARGS__);
template<typename T> void MACRO_VAR_Scan(T& t) { std::cin >> t; }
template<typename First, typename...Rest>void MACRO_VAR_Scan(First& first, Rest&...rest) { std::cin >> first; MACRO_VAR_Scan(rest...); }
#define VEC_ROW(type, n, ...)std::vector<type> __VA_ARGS__;MACRO_VEC_ROW_Init(n, __VA_ARGS__); for(int i=0; i<n; ++i){MACRO_VEC_ROW_Scan(i, __VA_ARGS__);}
template<typename T> void MACRO_VEC_ROW_Init(int n, T& t) { t.resize(n); }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Init(int n, First& first, Rest&...rest) { first.resize(n); MACRO_VEC_ROW_Init(n, rest...); }
template<typename T> void MACRO_VEC_ROW_Scan(int p, T& t) { std::cin >> t[p]; }
template<typename First, typename...Rest>void MACRO_VEC_ROW_Scan(int p, First& first, Rest&...rest) { std::cin >> first[p]; MACRO_VEC_ROW_Scan(p, rest...); }
#define VEC(type, c, n) std::vector<type> c(n);for(auto& i:c)std::cin>>i;
#define MAT(type, c, m, n) std::vector<std::vector<type>> c(m, std::vector<type>(n));for(auto& r:c)for(auto& i:r)std::cin>>i;

// output
#define OUT(d) std::cout<<d;
#define FOUT(n, d) std::cout<<std::fixed<<std::setprecision(n)<<d;
#define SOUT(n, c, d) std::cout<<std::setw(n)<<std::setfill(c)<<d;
#define SP std::cout<<" ";
#define TAB std::cout<<"\t";
#define BR std::cout<<"\n";
#define SPBR(i, n) std::cout<<(i + 1 == n ? '\n' : ' ');
#define ENDL std::cout<<std::endl;
#define FLUSH std::cout<<std::flush;
#define SHOW(d) {std::cerr << #d << "\t:" << d << "\n";}
#define SHOWVECTOR(v) {std::cerr << #v << "\t:";for(const auto& xxx : v){std::cerr << xxx << " ";}std::cerr << "\n";}
#define SHOWVECTOR2(v) {std::cerr << #v << "\t:\n";for(const auto& xxx : v){for(const auto& yyy : xxx){std::cerr << yyy << " ";}std::cerr << "\n";}}
#define SHOWQUEUE(a) {auto tmp(a);std::cerr << #a << "\t:";while(!tmp.empty()){std::cerr << tmp.front() << " ";tmp.pop();}std::cerr << "\n";}

// utility
#define ALL(a) (a).begin(),(a).end()
#define FOR(i, a, b) for(int i=(a);i<(b);++i)
#define RFOR(i, a, b) for(int i=(b)-1;i>=(a);--i)
#define REP(i, n) for(int i=0;i<int(n);++i)
#define RREP(i, n) for(int i=int(n)-1;i>=0;--i)
#define FORLL(i, a, b) for(ll i=ll(a);i<ll(b);++i)
#define RFORLL(i, a, b) for(ll i=ll(b)-1;i>=ll(a);--i)
#define REPLL(i, n) for(ll i=0;i<ll(n);++i)
#define RREPLL(i, n) for(ll i=ll(n)-1;i>=0;--i)
#define IN(a, x, b) (a<=x && x<b)
template<typename T> inline T CHMAX(T& a, const T b) { return a = (a < b) ? b : a; }
template<typename T> inline T CHMIN(T& a, const T b) { return a = (a > b) ? b : a; }
#define EXCEPTION(msg) throw std::string("Exception : " msg " [ in ") + __func__ + " : " + std::to_string(__LINE__) + " lines ]"
#define TRY(cond, msg) try {if (cond) EXCEPTION(msg);}catch (std::string s) {std::cerr << s << std::endl;}
void CHECKTIME(std::function<void()> f) { auto start = std::chrono::system_clock::now(); f(); auto end = std::chrono::system_clock::now(); auto res = std::chrono::duration_cast<std::chrono::nanoseconds>((end - start)).count(); std::cerr << "[Time:" << res << "ns  (" << res / (1.0e9) << "s)]\n"; }

// test
template<class T> std::vector<std::vector<T>> VV(int n) {
	return std::vector<std::vector<T>>(n);
}
template<class T> std::vector<std::vector<T>> VV(int n, int m, T init = T()) {
	return std::vector<std::vector<T>>(n, std::vector<T>(m, init));
}
template<typename S, typename T>
std::ostream& operator<<(std::ostream& os, std::pair<S, T> p) {
	os << "(" << p.first << ", " << p.second << ")"; return os;
}

// type/const

//#define int ll
using ll = long long;
using ull = unsigned long long;
using ld = long double;
using PAIR = std::pair<int, int>;
using PAIRLL = std::pair<ll, ll>;
constexpr int INFINT = 1 << 30;                          // 1.07x10^ 9
constexpr int INFINT_LIM = (1LL << 31) - 1;              // 2.15x10^ 9
constexpr ll INFLL = 1LL << 60;                          // 1.15x10^18
constexpr ll INFLL_LIM = (1LL << 62) - 1 + (1LL << 62);  // 9.22x10^18
constexpr double EPS = 1e-9;
constexpr int MOD = 1000000007;
constexpr double PI = 3.141592653589793238462643383279;

template<class T, size_t N> void FILL(T(&a)[N], const T& val) { for (auto& x : a) x = val; }
template<class ARY, size_t N, size_t M, class T> void FILL(ARY(&a)[N][M], const T& val) { for (auto& b : a) FILL(b, val); }
template<class T> void FILL(std::vector<T>& a, const T& val) { for (auto& x : a) x = val; }
template<class ARY, class T> void FILL(std::vector<std::vector<ARY>>& a, const T& val) { for (auto& b : a) FILL(b, val); }



class PrimalDual {
	const int INF = (1LL << 31) - 1;
	struct Edge { int to, cap, cost, rev; };

	int N;
	std::vector<std::vector<Edge>> g;
	std::vector<int> h, dist, preV, preE;

public:
	PrimalDual(int n) : N(n), g(n), h(n), dist(n), preV(n, -1), preE(n, -1) {}

	// fromからtoへの辺(容量cap, コストcost)を張る
	void addEdge(int from, int to, int cap, int cost) {
		g[from].emplace_back(Edge{ to, cap, cost, (int)g[to].size() });
		g[to].emplace_back(Edge{ from, 0, -cost, (int)g[from].size() - 1 });
	}

	// sからtに流量fの最小費用流を求める (流せなければ-1)
	int minCostFlow(int s, int t, int f) {
		int res = 0;
		h.assign(N, 0);
		using P = std::pair<int, int>;
		while (f > 0) {
			std::priority_queue<P, std::vector<P>, std::greater<P>> pq;
			dist.assign(N, INF);
			dist[s] = 0;
			pq.push(P(0, s));
			while (!pq.empty()) {
				P p = pq.top(); pq.pop();
				int v = p.second;
				if (dist[v] < p.first) continue;
				for (int i = 0; i < g[v].size(); ++i) {
					Edge& e = g[v][i];
					if (e.cap > 0 && dist[e.to] > dist[v] + e.cost + h[v] - h[e.to]) {
						dist[e.to] = dist[v] + e.cost + h[v] - h[e.to];
						preV[e.to] = v;
						preE[e.to] = i;
						pq.push(P(dist[e.to], e.to));
					}
				}
			}
			if (dist[t] == INF) return -1;
			for (int v = 0; v < N; ++v) h[v] += dist[v];

			// s-t間の最短経路に流す
			int d = f;
			for (int v = t; v != s; v = preV[v]) {
				d = std::min(d, g[preV[v]][preE[v]].cap);
			}
			f -= d;
			res += d * h[t];
			for (int v = t; v != s; v = preV[v]) {
				Edge& e = g[preV[v]][preE[v]];
				e.cap -= d;
				g[v][e.rev].cap += d;
			}
		}
		return res;
	}
};

signed main() {
	INIT;

	VAR(int, n, m, f);
	PrimalDual pd(n);
	REP(i, m) {
		VAR(int, u, v, c, d);
		pd.addEdge(u, v, c, d);
	}
	OUT(pd.minCostFlow(0, n - 1, f))BR;
	return 0;
}


Measured memory_bytes: 3248