#include <bits/stdc++.h>
#define ll long long 
using namespace std;
const int N = 5e5 + 100;
int n;
ll d[N], dt = 1e7, t;
int main(){
    scanf("%d%lld",&n,&t);
    for(int i = 1;i <= n;i++){
        ll x, y;scanf("%lld%lld",&x,&y);
        x -= dt;
        d[i] = x * x + y * y;
    }
    sort(d + 1, d + 1 + n);
    ll Mx = sqrtl(d[n]) + 10;
    int ans = n;
    for(int i = 1;i <= n;i++){
        if(d[i] <= dt * dt){
            dt += t;
            if(dt >= Mx) dt = Mx;
        }
        else{ans = i - 1;break;}
    }
    printf("%d\n",ans);
    return 0;
}