#include <bits/stdc++.h> using namespace std; int main() { int n,x,y,r,ans=0; cin>>n>>x>>y>>r; for(int i=1;i<=n;i++) { int a,b; cin>>a>>b; double d=sqrt((a-x)(a-x)+(b-y)(b-y)); if(d<=r) ans++; } cout<<ans<<endl; return 0; }