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

const int N = 2e5 + 5;
typedef long long LL;

vector<int> e[N];
int w[N], mn[N];
int d[N];
bool vis[N];
int L;
int n, m, A, B;

void dij1(){

    memset(d, 63, (n + 2) * sizeof(int));
    memset(vis, 0, (n + 2) * sizeof(bool));
    priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> q;
    d[1] = 0;
    q.push({0, 1});

    while(!q.empty()){
        int x = q.top().second;
        q.pop();

        if(vis[x])continue;
        // if(w[x] + 1ll * d[x] * (B - A) >= L)continue;
        vis[x] = 1;

        for(int u : e[x]){
            if(d[u] > d[x] + 1 && w[u] + 1ll * d[x] * (B - A) < L){
                d[u] = d[x] + 1;
                q.push({d[u], u});
            }
        }
    }
}

bool check(){
    memset(vis, 0, (n + 2) * sizeof(bool));
    priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> q;

    int cnt = 0;

    vis[1] = 1;
    for(int u : e[1]){
        q.push({w[u], u});
        vis[u] = 1;
    }

    while(!q.empty()){
        int x = q.top().second;
        q.pop();

        if(w[x] >= L + 1ll * (A - B) * cnt)return 0;
        if(x == n)return 1;
        cnt ++;

        for(int u : e[x]){
            if(!vis[u]){
                q.push({w[u], u});
                vis[u] = 1;
            }
        }
    }

    return 0;
}

void dij2(){
    memset(d, 63, (n + 2) * sizeof(int));
    memset(vis, 0, (n + 2) * sizeof(bool));



    priority_queue<pair<int, int>, vector<pair<int, int>>, greater<pair<int, int>>> q;
    d[1] = 0;
    q.push({0, 1});

    while(!q.empty()){
        int x = q.top().second;
        q.pop();

        if(vis[x])continue;
        vis[x] = 1;

        for(int u : e[x]){
            if(d[u] > max(d[x] + 1, mn[u] + 1)){
                d[u] = max(d[x] + 1, mn[u] + 1);
                q.push({d[u], u});
            }
        }
    }
}

int T;
int idx = 0;

void solve(){
    idx ++;
    scanf("%d%d%d%d", &n, &m, &A, &B);
    for(int i = 1; i <= n; i ++)e[i].clear();

    if(idx == 559)printf("%d %d %d %d\n", n, m, A, B);

    for(int i = 1; i <= m; i ++){
        int a, b;
        scanf("%d%d", &a, &b);
        e[a].push_back(b);
        e[b].push_back(a);
        if(idx == 559)printf("%d %d\n", a, b);
    }

    scanf("%d", &L);
    if(idx == 559)printf("%d ", L);
    for(int i = 2; i <= n; i ++){
        scanf("%d", &w[i]);
        if(idx == 559)printf("%d ", w[i]);
        w[i] += B;
    }

    if(B >= A){
        dij1();
        if(T != 100000){
            if(d[n] >= 1e8)puts("-1");
        else printf("%d\n", d[n]);
        }
        
    }
    else {
        // printf("%d\n", w[110000000]);
        if(!check()){
            if(T != 100000)puts("-1");
            return ;
        }

        for(int i = 2; i <= n; i ++){
            if(w[i] < L)mn[i] = 0;
            else {
                int t = w[i] - L + 1;
                mn[i] = t / (A - B);
                if(t % (A - B))mn[i] ++;
            } 
        }

        dij2();

        if(T != 100000)printf("%d\n", d[n]);
    }
}

int main(){
    // freopen("easy.in", "r", stdin);
    // freopen("easy.out", "w", stdout);
    
    scanf("%d", &T);
    for(int t = 1; t <= T; t ++){
        solve();
    }
}