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// Artur Kraska, II UWr

#include <bits/stdc++.h>

#define forr(i, n)                  for(int i=0; i<n; i++)
#define FOREACH(iter, coll)         for(auto iter = coll.begin(); iter != coll.end(); ++iter)
#define FOREACHR(iter, coll)        for(auto iter = coll.rbegin(); iter != coll.rend(); ++iter)
#define lbound(P,R,PRED)            ({typeof(P) X=P,RRR=(R), PPP = P; while(PPP<RRR) {X = (PPP+(RRR-PPP)/2); if(PRED) RRR = X; else PPP = X+1;} PPP;})
#define testy()                     int _tests; scanf("%d", &_tests); FOR(_test, 1, _tests)
#define CLEAR(tab)                  memset(tab, 0, sizeof(tab))
#define CONTAIN(el, coll)           (coll.find(el) != coll.end())
#define FOR(i, a, b)                for(int i=a; i<=b; i++)
#define FORD(i, a, b)               for(int i=a; i>=b; i--)
#define MP                          make_pair
#define PB                          push_back
#define deb(X)                      X;

#define M 1000000007
#define INF 1000000007

using namespace std;

int n, m, a, b, x, y, teraz;
long long res, res1 = 1;
char slowo[5];
vector <int> l[500007];
vector <pair<int, int>> v;
int byl[500007], morze, num[500007], poczatki[500007];
long long tab[500007], suma[500007];

void dfs(int nr)
{
//    cout << "odpala sie dfs w " << nr << endl;
    byl[nr] = teraz;
    if(nr > a && nr <= a+b)
    {
//        cout << "doszedl do morza w " << nr << endl;
        morze = min(morze, nr);
    }
    for(int s : l[nr])
    {
        if(byl[s] != teraz)
            dfs(s);
    }
}

int main()
{
    scanf("%d %d %d %d", &n, &m, &a, &b);
    forr(i, m)
    {
        scanf("%d %s %d", &x, slowo, &y);
        l[x].PB(y);
        if(slowo[1] == '-')
            l[y].PB(x);
    }

    teraz++;
    FOR(i, 1, a) // <<< tu cos nie gra...
    {
//        cout << "probuje dla i = " << i <<  endl;
        teraz++;
        dfs(i);
    }

    int nn = 0;
    FOR(i, a+1, a+b)
    {
        num[i] = nn;
        if(byl[i] != 0)
            nn++;
        else
            res1 = (res1*2)%M;
    }

    FOR(i, 1, a)
    {
//        cout << "sprawdza " << i << endl;
        teraz++;
        morze = INF;
        dfs(i);
        int p = morze, k = morze;
        while(k < a+b && (byl[k+1] == teraz || byl[k+1] == 0))
            k++;
        while(byl[k] == 0)
            k--;

        while(p > a+1 && (byl[p-1] == teraz || byl[p-1] == 0))
            p--;
        if(p == a+1 && k < a+b && (byl[a+b] == teraz || byl[a+b] == 0))
            p = a+b;
        while(p > a+1 && (byl[p-1] == teraz || byl[p-1] == 0))
            p--;
        while(p <= a+b && byl[p] == 0)
            p++;
        if(p == a+b+1)
            p = a+1;
        while(byl[p] == 0)
            p++;

//        cout << "przedzial dla " << i << " to od " << p << " do " << k;
        p = num[p];
        k = num[k];
//        cout << ", po przenumerowaniu od " << p << " do " << k << endl;
        v.PB(MP(p, k));
    }

    FOR(start, 0, nn-1)
    {
        forr(i, nn+3)
        {
            tab[i] = suma[i] = 0;
            poczatki[i] = -1;
        }
//        cout << "startuje w " << start << endl;
        for(auto el : v)
        {
            int p = el.first;
            int k = el.second;
            if(!(k >= start && (p <= start || p > k)))
            {
//                cout << "doklada przedzial od " << p << " do " << (k>=p ? k : nn-1) << endl;
                if(k >= p)
                    poczatki[k] = max(poczatki[k], p);
                else
                    poczatki[nn-1] = max(poczatki[nn-1], p);
            }
        }
        FOR(i, 1, nn-1)
            poczatki[i] = max(poczatki[i], poczatki[i-1]);

//        forr(i, nn)
//            cout << "poczatki[" << i << "] = " << poczatki[i] << endl;

        if(start > 0 && poczatki[start-1] != -1)
        {
//            cout << "wyskakuje" << endl;
            continue;
        }
        tab[start] = 1;
        suma[start] = 1;
        FOR(i, start+1, nn)
        {
            tab[i] = (suma[i-1] - (poczatki[i-1] <= 0 ? 0 : suma[poczatki[i-1]-1]) + M) % M;
            suma[i] = (suma[i-1] + tab[i]) % M;
//            cout << "tab[" << i << "] = " << tab[i] << endl;
        }
        res = (res + tab[nn]) % M;
    }

    printf("%lld\n", (res * res1)%M);

    return 0;
}