#include <algorithm>
#include <iostream>
using namespace std;
const long long inf = 999999999999999;
long long n, s, l, h[200005], a[200005], k[200005], ans = inf;
bool can()
{
    long long sum = 0;
    for (int i = 1; i <= n; i++)
    {
        if (k[i] >= l)
        {
            sum += k[i];
        }
        if (sum >= s)
        {
            return true;
        }
    }
    return false;
}
void binary(long long l, long long r)
{
    if (l == r)
    {
        return;
    }
    long long mid = (l + r) / 2;
    for (int i = 1; i <= n; i++)
    {
        k[i] = h[i] + a[i] * mid;
    }
    if (can())
    {
        if (mid < ans)
        {
            ans = mid;
        }
        binary(l, mid);
    }
    else
    {
        binary(mid + 1, r);
    }
}
int main()
{
    cin >> n >> s >> l;
    for (int i = 1; i <= n; i++)
    {
        cin >> h[i];
    }
    for (int i = 1; i <= n; i++)
    {
        cin >> a[i];
    }
    binary(0, inf);
    cout << ans;
    return 0;
}