#include <bits/stdc++.h>

using namespace std;

#define REP(i,a,b) for(int i=a;i<(int)b;i++)
#define rep(i,n) REP(i,0,n)

const long long Inf = numeric_limits<long long>::max() / 4;

namespace flow_algorithm
{
  template<class Flow>
  struct edge
  {
    int to;
    Flow cap, rev;
  };
  /*
    template<class Flow>
    using edges = vector<edge<Flow>>;
    
    template<class Flow>
    using graph = vector<edges<Flow>>;
  */
  
  typedef vector<edge<long long>> edges;
  typedef vector<edges> graph;
  
  template<class Flow>
  class dinic
  {
  private:
    int V;
    //    graph<Flow> g;
    graph g;
    vector<int> level;
    vector<int> iter;
    
  public:
    //    Flow static constexpr Inf = numeric_limits<Flow>::max() / 4;
    
  private:
    
    void bfs(int s)
    {
      rep(i, V) level[i] = -1;
      queue<int> q;
      q.push(s);
      level[s] = 0;
      while(!q.empty()) {
        int curr = q.front(); q.pop();
        rep(i, g[curr].size()) {
          edge<Flow>& e = g[curr][i];
          if(level[e.to] != -1) { continue; }
          if(e.cap <= 0) { continue; }
          level[e.to] = level[curr] + 1;
          q.push(e.to);
        }
      }
    }
    
    Flow dfs(int curr, int tar, Flow flow)
    {
      if(curr == tar) { return flow; }
      for(int &i = iter[curr]; i<(int)g[curr].size(); i++) {
        edge<Flow>& e = g[curr][i];
        if(e.cap <= 0) { continue; }
        if(level[curr] >= level[e.to]) { continue; }
        Flow d = dfs(e.to, tar, min(flow, e.cap));
        if(d <= 0) { continue; }
        e.cap -= d;
        g[e.to][e.rev].cap += d;
        return d;
      }
      return 0;
    }
    
  public:
    
    dinic(int V_)
    {
      V = V_;
      g.resize(V);
      level.resize(V);
      iter.resize(V);
    }
    
    void add_edge(int from, int to, Flow cap)
    {
      g[from].push_back({to, cap, (Flow)g[to].size()});
      g[to].push_back({from, 0, (Flow)g[from].size()-1});
    }
    
    Flow max_flow(int src, int dest)
    {
      Flow flow = 0;
      for(;;) {
        bfs(src);
        if(level[dest] < 0) { return flow; }
        rep(i, V) iter[i] = 0;
        Flow f;
        while((f = dfs(src, dest, Inf)) > 0) {
          flow += f;
        }
      }
    }
    
  };
  
  
}

typedef long long ll;

int main() {
  
  int N; ll M, L;
  while(cin >> N >> M >> L) {
    ll g[N][N];
    rep(i, N) rep(j, N) g[i][j] = Inf;
    
    rep(i, M) {
      int a, b, d; cin >> a >> b >> d; a--, b--;
      g[a][b] = g[b][a] = d;
    }
    
    rep(k, N) rep(i, N) rep(j, N) {
      if(g[i][k] == Inf && g[k][j] == Inf) { continue; }
      g[i][j] = min(g[i][j], g[i][k]+g[k][j]);
    }
    
    rep(i, N) { g[i][i] = 0; }
    
    int const SRC = 2*N+1, SINK = 2*N+2;
    
    flow_algorithm::dinic<ll> dn(2*N+10);
    
    vector<int> ps(N);
    rep(i, N) {
      cin >> ps[i];
      dn.add_edge(SRC, i, ps[i]);
    }
    
    rep(i, N) rep(j, N) {
      //      if(i == j) { continue; }
      if( g[i][j] < L ) {
        dn.add_edge(i, N+j, Inf);
      }
    }
    
    rep(i, N) {
      ll K; cin >> K;
      dn.add_edge(N+i, SINK, K);
    }
    
    cout << dn.max_flow(SRC, SINK) << endl;
  }
  
  return 0;
}

Measured memory_bytes: 1852