#include<iostream>
#include<vector>
#include<algorithm>
#include<stdio.h>
#include<time.h>
#include<set>
#include<map>
#include<utility>
#include<queue>
#include<limits>

using namespace std;


class Edge{
public:
  int from;
  int to;
  int flow;
  Edge(){
  }
  Edge(int f,int t,int d){
    from = f;
    to   = t;
    flow = d;
  }
  bool operator==(const Edge &e){
    return this->from == e.from && this->to ==e.to;
  }
};

class Shortest_path_result{
public:
  int sum_of_cost;
  vector<int> path;
  vector<int> distance;
  vector<int> predecessor;
  Shortest_path_result(){
  }
};


class Graph{
public:
  int INF;
  int n;
  vector<set<int> > vertices_list;
  vector<map<int,int > > cost_list;
  vector<map<int,int > > capacity_list;
  vector<int> potential_list;

  Graph(){
  }
  Graph(int n){//nは頂点数
    INF = 2e9;
    this->n=n;
    //各種リストを集合
    //n個の空集合を挿入
    vertices_list.insert(vertices_list.begin(),n,set<int>());
    cost_list.insert(cost_list.begin(),n,map<int,int>());
    capacity_list.insert(capacity_list.begin(),n,map<int,int>());
    potential_list = vector<int>(n,0);
  }

  Graph clone(void){
    Graph g = Graph(this->n);
    g.vertices_list = this->vertices_list;
    g.cost_list = this->cost_list;
    g.capacity_list = this->capacity_list;
    g.potential_list = this->potential_list;
    return g;
  }

  //b->eの辺を挿入 頂点番号は0オリジン
  void insert_edge(int b,int e,int cost,int capacity){
    vertices_list[b].insert(e);
    cost_list[b][e] = cost;
    capacity_list[b][e] = capacity;
  }
  void delete_edge(int b,int e){
    //b-eな辺を削除
    vertices_list[b].erase(e);
    cost_list[b].erase(e);
    capacity_list[b].erase(e);
  }

  //頂点番号aの次数を返す
  int degree_of_vertex(int a){
    return vertices_list[a].size();
  }

  //a-bな辺があるか調査
  bool edge_search(int a,int b){
    return vertices_list[a].find(b)!=vertices_list[a].end();
  }

  //頂点aとbに対してa-bとなる道が存在するかどうか調査
  bool path_search(int a,int b,set<int> visited=set<int>()){
    visited.insert(a);
    set<int>::iterator itr;
    for(itr=vertices_list[a].begin();itr!=vertices_list[a].end();itr++){
      if((*itr)==b){
        return true;
      }
      if(visited.find(*itr)==visited.end()){ //行ったこと無いなら
        if(path_search(*itr,b,visited)){//再帰
          return true;
        }
      }
    }
    return false;
  }
  //start から goalまでの最短経路を探索:
  Shortest_path_result solve_dijkstra(int start,int goal){
    set<int> visited = set<int>();
    vector<int> distance = vector<int>(n,INF);
    vector<int> predecessor = vector<int>(n);
    priority_queue<pair<int,int>,vector<pair<int,int> >,greater<pair<int,int> > > pq;
    pq.push(pair<int,int>(0,start)); //<始点からの距離,頂点>
    while(!pq.empty()){
      pair<int,int> p = pq.top();
      pq.pop();
      int nv = p.second;//今の場所
      // いい道じゃなかったら
      if(distance[nv] < p.first){
        continue;
      }
      distance[nv] = p.first;
      // いい道が見つかったら
      //nvから伸びる点をキューへ
      for(set<int>::iterator itr = vertices_list[nv].begin();itr!=vertices_list[nv].end();itr++){
        int next = (*itr);
        if(distance[next] > distance[nv] + cost_list[nv][next]){
          distance[next] = distance[nv] + cost_list[nv][next];
          predecessor[next] = nv;
          pq.push(pair<int,int>(distance[next],next));
        }
      }
    }
    //答えを整形
    Shortest_path_result result;
    result.path = vector<int>();
    if(distance[goal]==INF){
    }else{
      result.path.push_back(goal);
      if(start != goal){
        while(true){
          int now = result.path.back();
          int pre = predecessor[now];
          result.path.push_back(pre);
          if(pre == start){
            reverse(result.path.begin(),result.path.end());
            break;
          }
        }
      }
    }
    result.sum_of_cost = distance[goal];
    result.distance = distance;
    result.predecessor = predecessor;
    return result;
  }
  //mcf2
  pair<int,vector<Edge> > solve_mincostflow(int s,int t, int flow_size){
    int answer_cost = 0;
    vector<map<int,int> > origin_cost = cost_list;
    vector<map<int,int> > answer_flow = vector<map<int,int> >(n,map<int,int>());

    Graph residual_g = clone();

    while(flow_size>0){
      Shortest_path_result res;
      vector<int> path;
      int min_capa = INF;
      //補助ネットワークから最小コストのパスを検索
      res = residual_g.solve_dijkstra(s,t);
      path = res.path;
      //tに到達不可能だったら
      if(res.distance[t] ==INF){
        //cerr << "infeasible" << endl;
        return pair<int,vector<Edge> >(-1,vector<Edge>());
      }
      //ポテンシャルを更新
      for(int i = 0;i<n;i++){
        potential_list[i] = potential_list[i] - res.distance[i];
      }

      //流せる量を計算
      min_capa =INF;
      for(int to = t; to != s; to = res.predecessor[to]){
        int from = res.predecessor[to];
        min_capa = min(min_capa,residual_g.capacity_list[from][to]);
      }
      min_capa = min(min_capa,flow_size);
      //flow_sizeをへらす
      flow_size -= min_capa;

      //フローを記録
      for(int to = t; to != s; to = res.predecessor[to]){
        int from = res.predecessor[to];
        if(vertices_list[from].find(to)!=vertices_list[from].end()){
          if(answer_flow[from].find(to) != answer_flow[from].end() ){//from -> toがあったら
            answer_flow[from][to] += min_capa;
          }else{//初流し
            answer_flow[from][to] = min_capa;
          }
        }else{//逆向きに流れる = 減らす
          answer_flow[to][from] -= min_capa;
          if(answer_flow[to][from] == 0){
            answer_flow[to].erase(from);
          }
        }
      //残余ネットワークの作成
        int nflw = min_capa;//from->toにnflwだけ流れてる
        int old_capa = residual_g.capacity_list[from][to];
        //元の辺を削除
        residual_g.delete_edge(from,to);
        //to -> fromにnflwだけながす
        if(residual_g.vertices_list[to].find(from)!=residual_g.vertices_list[to].end()){//流した痕跡あり
          residual_g.capacity_list[to][from] += nflw;
        }else{//流した痕跡なし(新たに逆辺を追加
          residual_g.insert_edge(to,from,0,nflw);
        }
        //from->toの辺の容量を減らす
        if(old_capa != nflw){//あまりあり
          residual_g.insert_edge(from,to,0,old_capa - nflw);
        }
      }
      //辺のコストの更新
      //残余ネットワークの全ての辺のコストを更新
      set<int>::iterator itr;
      for(int i=0;i<n;i++){
        for(itr= residual_g.vertices_list[i].begin();itr!=residual_g.vertices_list[i].end();itr++){
          int from = i;
          int to = *itr;
          if(origin_cost[from].find(to)!=origin_cost[from].end()){
            residual_g.cost_list[from][to] = origin_cost[from][to] - potential_list[from] + potential_list[to];
          }else{
            residual_g.cost_list[from][to] = -1*origin_cost[to][from] - potential_list[from] + potential_list[to];
          }
        }
      }
    }
    //print();
    //解を整形

    vector<Edge> return_flow = vector<Edge>();
    answer_cost = 0;
    for(int i=0;i<n;i++){
      map<int,int>::iterator itr;
      for(itr=answer_flow[i].begin();itr!=answer_flow[i].end();itr++){
        int from =i; int to = itr->first;
        if(origin_cost[from].find(to) == origin_cost[from].end()){//元々はない辺=逆辺
          ///元々存在する辺の流量をへらす
          answer_flow[to][from] -= itr->second;
        }
      }
    }
    for(int i=0;i<n;i++){
      map<int,int>::iterator itr;
      for(itr=answer_flow[i].begin();itr!=answer_flow[i].end();itr++){
        int from =i; int to = itr->first;
        if(origin_cost[from].find(to) != origin_cost[from].end()){//from->toは元々ある辺
          answer_cost += itr->second * origin_cost[from][to];
          return_flow.push_back(Edge(from,to,itr->second));
        }
      }
    }

    return pair<int,vector<Edge> >(answer_cost,return_flow);

  }





  //出力
  void print(void){
    int i=0;
    vector<set<int> >::iterator itr;
    set<int>::iterator itr_c;
    for(itr=vertices_list.begin();itr!=vertices_list.end();itr++){
      cout << i << ":";
      for(itr_c=(*itr).begin();itr_c!=(*itr).end();itr_c++){
        cout << *itr_c << "(" <<capacity_list[i][*itr_c] <<")" << ",";
      }
      i++;
      cout << endl;
    }
  }
};


int main(){
  int v,e,f;
  std::cin >> v >> e >> f;
  Graph g = Graph(v);
  for(int i=0;i<e;i++){
    int from,to,capa,cost;
    cin >>from >> to >> capa >> cost ;
    g.insert_edge(from,to,cost,capa);
  }
  std::cout << g.solve_mincostflow(0,v-1,f).first << endl;

  return 0;
}


Measured memory_bytes: 3552