#include <iostream>
#include <algorithm>
using namespace std;

struct node {
    int h, s;
}a[5010];

bool cmp(node x,node y){
    return x.s < y.s;
}

int main() {
    int n, st;
    int benchHeight, armHeight;
    cin >> n >> st;
    cout<<n<<' '<<st<<endl;
    cin >> benchHeight >> armHeight;
    int sum = benchHeight + armHeight;
    for (int i = 0; i < n; i++) {
        cin >> a[i].h >> a[i].s;
    }
    sort(a, a + n, cmp);
    int cnt = 0;
    for (int i = 0; i < n && st > 0; i++) {  // 修改为for循环，加入遍历完整个数组的判断
        if (st <= a[i].s) {
            if (sum < a[i].h){
                continue;
            }
            else{
                if (a[i].s != 0){
                    st -= a[i].s;
                }
                cnt++;
            }
        }
    }
    cout << cnt << endl;
    return 0;
}