Xor sum

input/code.cpp: In function 'int main()':
input/code.cpp:21:19: warning: comparison of integer expressions of different signedness: 'int' and 'ull' {aka 'long long unsigned int'} [-Wsign-compare]
   21 |     for(int i=0; i<n; i++){
      |                  ~^~
input/code.cpp:26:23: warning: comparison of integer expressions of different signedness: 'int' and 'ull' {aka 'long long unsigned int'} [-Wsign-compare]
   26 |     for (int i = 0; i < q; ++i) {
      |                     ~~^~~
input/code.cpp:32:28: error: expected ';' before '}' token
   32 |         cout << sum << "\n"
      |                            ^
      |                            ;
   33 |     }
      |     ~

#pragma GCC optimize("Ofast")
 
#pragma GCC target("avx2,bmi,bmi2,popcnt,lzcnt")
 
#include <bits/stdc++.h>
using namespace std;
 
typedef unsigned long long ull;
 
const int MAXN = (int)1e5 + 1;
 
int xs[MAXN];
 
int main(){
    ull n, q;
    ios::sync_with_stdio(false);
    cout.tie(0);
 
    cin >> n >> q;
    
    for(int i=0; i<n; i++){
        cin >> xs[i];
    }
 
    int a, b;
    for (int i = 0; i < q; ++i) {
        cin >> a >> b;
        int sum = 0;
        for (int j = a - 1; a <= b - 1; ++j) {
            sum ^= xs[j];
        }
        cout << sum << "\n"
    }
 
    return 0;
}