#include <bits/stdc++.h>
using namespace std;
#define INF 1e12
const int N=1e6+5;
typedef pair<int,int> P;
typedef long long ll;
typedef pair<ll,ll>Pll;
typedef __int128 i128;
const ll mod=1e9+7;
typedef long double db;
const db eps=1e-10;
mt19937_64 rnd(time(0));
void solve(){
    int n,a,b,c;
    cin >> n;
    cin >> a >> b >> c;

    int ans=0;
    vector<P>arr(n);
    for(int i=0;i<n;i++) cin >> arr[i].first >> arr[i].second;
    int d;
    cin >> d;
    for(int i=0;i<n;i++){
        int tot=arr[i].first+arr[i].second;
        if(tot<c){
            arr[i].first=min(a,arr[i].first+d);
            tot=arr[i].first+arr[i].second;
            if(tot>=c) ans++;
        }
    }
    cout << ans  << "\n"; 
}
int main(){
    ios::sync_with_stdio(0);
    cin.tie(0);
    cout.tie(0);
    int t=1;
    //cin >> t;
    while(t--)
    solve();
}