Problem: Examples

Input

4 5 2
0 1 2 1
0 2 1 2
1 2 1 1
1 3 1 3
2 3 2 1


Output

6


Input




Output

Solution (in CPP):

Solution:
#include <stdio.h>
#include <iostream>
#include <vector>
#include <string>
#include <string.h>
#include <math.h>
#include <algorithm>
#include <queue>
using namespace std;

#define MAX_V 201
#define INF 1000000000

typedef pair<int, int> P;
struct edge{int to, cap, cost, rev;};
int V;
vector<edge> G[MAX_V];
int h[MAX_V];
int dist[MAX_V];
int prevv[MAX_V];
int preve[MAX_V];

void ae(int from, int to, int cap, int cost){
  G[from].push_back((edge){to, cap, cost, (int)G[to].size()});
  G[to].push_back((edge){from, 0, -cost, (int)G[from].size() - 1});
}

int minCostFlow(int s, int t, int f){
  int res = 0;
  memset(h,0,sizeof(h));
  while(f > 0){
    priority_queue<P, vector<P>, greater<P> > que;
    for(int i = 0; i < V; i++){
      dist[i] = INF;
    }
    dist[s] = 0;
    que.push(P(0,s));
    while(!que.empty()){
      P p = que.top(); que.pop();
      int v = p.second;
      if(dist[v] < p.first)continue;
      for(int i = 0; i < (int)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];
          prevv[e.to] = v;
          preve[e.to] = i;
          que.push(P(dist[e.to], e.to));
        }
      }
    }
    if(dist[t] == INF){
      return -1;
    }
    for(int v = 0; v < V; v++){
      h[v] += dist[v];
    }
    int d = f;
    for(int v = t; v != s; v = prevv[v]){
      d = min(d, G[prevv[v]][preve[v]].cap);
    }
    f -= d;
    res += d * h[t];
    for(int v = t; v != s; v = prevv[v]){
      edge &e = G[prevv[v]][preve[v]];
      e.cap -= d;
      G[v][e.rev].cap += d;
    }
  }
  return res;
}

int main(){
  int v,e,f;
  cin>>v>>e>>f;
  V=v;
  edge z;
  for(int i=0;i<e;i++){
    cin>>z.to>>z.cap>>z.cost>>z.rev;
    ae(z.to,z.cap,z.cost,z.rev);
  }
  cout << minCostFlow(0,v-1,f) << endl;
  return 0;
}