Help me in solving BALL_GAME problem

My issue

can someone tell me why this give SIGSEGV error

My code

#include<bits/stdc++.h>
using namespace std;
                         
#define fastio()  ios_base::sync_with_stdio(false), cin.tie(NULL); 

using lld = long double; 
using ll=long long;

int main() {
	// your code goes here
   fastio() 
	ll t;
	cin>>t;
	while(t--){
	    int n;
	    cin>>n;
	    vector<ll>a,b;
	   for(int i=0;i<n;i++){
	       ll x;
	       cin>>x;
	       a.push_back(x);
	   }
	    for(int i=0;i<n;i++){
	       ll x;
	       cin>>x;
	       b.push_back(x);
	   }
	    vector<pair<ll,ll>>v;
	    for(int i=0;i<n;i++){
	        v.push_back(make_pair(a[i],b[i]));
	    }
	    sort(v.begin(),v.end());
	    
	    vector<lld>time;
	     for(int i=0;i<n;i++){
	         ll x1=v[i].first;
	         ll x2=v[i].second;
	       time[i]=x1/(double)x2;
	    }
	 
	    ll last_time=time[n-1];
	    ll ans=1;
	    for(ll i=n-2;i>=0;i--){
	       if(time[i]<last_time){
	          ans++;
	          last_time=time[i];
	       }
	    }
	    cout<<ans<<endl;
	}
  return 0;
}

Problem Link: Ball Game Practice Coding Problem