XOR from L to R using BIT

// KEEP IT SIMPLE //
#include<bits/stdc++.h>
using namespace std;
#define int long long
#define MAX 100
const int inf = 9e18;
const double pi = acos(-1.0);
const int M = 1e9 + 7;
const int N = 1e5 + 5;
int gccd(int a, int b){ if(a == 0) return b; return gccd(b % a, a); }
int power(int x, unsigned int y){ int temp; if( y == 0) return 1; temp = power(x, y/2);
                  if (y%2 == 0) return temp * temp; else return x * temp * temp;
}
int res[1000005], n;
int BITree[1000005];
int getSum(int index)
{
    int sum = 0;
    while (index>0)
    {
        sum ^= BITree[index];
        index -= index & (-index);
    }
    return sum;
}
void updateBIT(int index, int val)
{
    while (index <= n)
    {
       BITree[index] ^= val;
       index += index & (-index);
    }
}
int32_t main()
{
   ios_base::sync_with_stdio(0);cin.tie(NULL);cout.tie(NULL);
   cin >> n;
   for(int i = 1 ; i <= n; i++)
   {
      cin >> res[i];
      updateBIT(i, res[i]);
   }
   int q;
   cin >> q;
   while(q--)
   {
      int l, r, pos;
      cin >> l >> r >> pos;
      int ans = getSum(r) ^ getSum(l - 1);
      int pro(0), p = ans;
      while(ans)
      {
         ans >>= 1;
         pro <<= 1;
         pro |= 1;
      }
      //cout << p << " " << pro << endl;
      if(p == pro)
      {
         cout << -1 << endl;
      }
      else
      {
         cout << (p ^ pro) << endl;
         updateBIT(pos, res[pos]);
         res[pos] = (p ^ pro);
         updateBIT(pos, res[pos]);
      }
   }
   return 0;
}