Help me in solving CHMOD problem

help
,
1

why am i getting runtime error?? can anuone help me

#include<bits/stdc++.h>
using namespace std;


void kre(vector<int> &a,vector<long long> &prefx)
{
    prefx.push_back(a[0]);
    for(int i=1;i<a.size();i++)
    {
        prefx.push_back(prefx[i-1]*a[i] *1LL);
    }
   

}

int main() {
   
    int n;
    cin >> n;
    vector<int> a(n);
    vector<long long > prefix;
    for (auto &it : a){cin >> it;}
    kre(a,prefix);
   
    int t;
    cin >> t;
    while(t--)
    {
        int l,r,m;
        long long x;
        cin >> l >> r>> m ;
        
        if(l<2) x = prefix[r-1] %m;
        else x=(prefix[r-1]/prefix[l-2])%m;
       
       cout<<x<<endl;


    }
}

Problem Link: CHMOD Problem - CodeChef