#include <bits/stdc++.h>

using namespace std;

typedef long long ll;

template <typename T>
void print(T *a, int n) {
    for (int i = 1; i < n; ++i)
        cout << a[i] << " " ;
    cout << a[n] << endl;
}

int n, m;
ll t;
char op;

const int N = 15;
bool poss[N][N];
bool vis[N][N];
int rmsk[N];
int cmsk[N];
ll p9[N];
int lookup[1 << 10];
pair<int, int> pts[N];

inline int lowbit(int x) {
    return x & (-x);
}

template<typename T>
int go(int idx, int nvis, T cur) {
    if (op == '+' && cur + 9 * (m - nvis) < t)
        return 0;
    if (op == '+' && cur + (m - nvis) > t)
        return 0;
    if (op == '*' && (cur * p9[m - nvis] < t || cur > t))
        return 0;
    int r = pts[idx].first;
    int c = pts[idx].second;
    if (nvis + 1 == m) {
        if (op == '+') {
            T last = t - cur;
            if (last > n || last <= 0) return 0;
            --last;
            if (rmsk[r] & (1 << last)) return 0;
            if (cmsk[c] & (1 << last)) return 0;
            return 1;
        }
        if (op == '*') {
            if (t % cur != 0)
                return 0;
            T last = t / cur;
            if (last > n) return 0;
            --last;
            if (rmsk[r] & (1 << last)) return 0;
            if (cmsk[c] & (1 << last)) return 0;
            return 1;
        }
    }
    int ans = 0;
    int msk = ((1 << n) - 1) ^ (cmsk[c] | rmsk[r]);
    for ( ; msk; msk -= lowbit(msk)) {
        int cur_v = lowbit(msk);
        int want = lookup[cur_v] + 1;
        vis[r][c] = true;
        rmsk[r] ^= cur_v;
        cmsk[c] ^= cur_v;
        T nxt = op == '+' ? cur + want : cur * want;
        ans += go(idx + 1, nvis + 1, nxt);
        vis[r][c] = false;
        rmsk[r] ^= cur_v;
        cmsk[c] ^= cur_v;
    }
    return ans;
}

int main() {
    ios_base::sync_with_stdio(false);
#ifdef CMU1
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
#endif
    double start_time = clock();
    cin >> n >> m >> t >> op;
    for (int i = 0; i < m; i++) {
        int r, c;
        cin >> r >> c;
        pts[i] = make_pair(r, c);
    }
    p9[0] = 1;
    for (int i = 1; i <= m; i++)
        p9[i] = 9LL * p9[i - 1];
    lookup[1] = 0;
    int now = 1;
    for (int i = 2; i <= 10; ++i) {
        now *= 2;
        lookup[now] = i - 1;
    }
    if (op == '-' || op == '/') {
        if (t > 10000) {
            cout << "0\n";
            exit(0);
        }
        int tot = 0;
        for (int i = 1; i <= n; i++) {
            for (int j = 1; j <= n; j++) {
                if (op == '-' && max(i, j) - min(i, j) == t)
                    tot++;
                if (op == '/' && i != j && min(i, j) * t == max(i, j)) {
                    tot++;
                }
            }
        }
        cout << tot << '\n';
        return 0;
    }
    int start = (op == '+') ? 0 : 1;
    ll ans = op == '+' ? go<int>(0, 0, start)
                       : go<ll>(0, 0, start);
    cout << ans << '\n';
    return 0;
}