#include <iostream>
using namespace std;
const int N = 1e6 + 6;
int o[N], p[N];
int n, d;
int ans = 0;
void dfs(int x, int l) {
    if (x == n + 1) {
        ans++;
        return;
    }
    if (o[x]) {
        dfs(x + 1, p[x] + d);
        dfs(x + 1, l);
    } else {
        if (p[x] <= l) dfs(x + 1, l);
        dfs(x + 1, l);
    }
}
int main() {
    freopen("Supervision.in", "r", stdin);
    freopen("Supervision.out", "w", stdout);
    cin >> n >> d;
    int cnt = 0;
    for (int i = 1; i <= n; i++) {
        cin >> p[i] >> o[i];
        cnt += o[i];
    }
    if (d == 0) {
        cout << (1 << cnt) - 1;
        return 0;
    }
    dfs(1, 0);
    cout << ans;
    return 0;
}