为什么 #15 T了

#include <iostream>
#define ls (ind<<1)
#define rs (ind<<1|1)
#define mid (l+r>>1)
using namespace std;
const int N = 1e5+9;
int a[N], tree[N][21], tag[N], n, q;
void pushup(int ind) {
  for (int i = 0; i < 21; i++) tree[ind][i] = tree[ls][i] + tree[rs][i];
}

void pushdown(int ind, int l, int r) {
  for (int i = 0; i < 21; i++) if ((tag[ind] >> i) & 1) tree[ls][i] = (mid - l + 1) - tree[ls][i], tree[rs][i] = (r - mid) - tree[rs][i];
  tag[ls] ^= tag[ind]; tag[rs] ^= tag[ind]; tag[ind] = 0;
}

void build(int ind, int l, int r) {
  if (l == r) {
    for (int i = 0; i < 21; i++) if ((a[l] >> i) & 1) tree[ind][i] = 1;
    return;
  }
  build(ls, l, mid); build(rs, mid + 1, r); pushup(ind);
}

void update(int ind, int l, int r, int cl, int cr, int val) {
  if (cl <= l && r <= cr) {
    for (int i = 0; i < 21; i++) if ((val >> i) & 1) tree[ind][i] = (r - l + 1) - tree[ind][i];
    tag[ind] ^= val;
    return;
  } 
  pushdown(ind, l, r);
  if (cl <= mid) update(ls, l, mid, cl, cr, val);
  if (mid < cr) update(rs, mid + 1, r, cl, cr, val);
  pushup(ind);
}

int sum(int ind, int l, int r, int cl, int cr) {
  long long res = 0;
  if (cl <= l && r <= cr) {
    for (int i = 0; i < 21; i++) res += 1ll * (1 << i) * tree[ind][i];
    return res;
  }
  pushdown(ind, l, r);
  if (cl <= mid) res += 1ll * sum(ls, l, mid, cl, cr);
  if (mid < cr) res += 1ll * sum(rs, mid + 1, r, cl, cr);
  return res;
}

signed main() {
  ios::sync_with_stdio(false); cin.tie(0); cout.tie(0);
  cin >> n; for (int i = 1; i <= n; i++) cin >> a[i];
  build(1, 1, n); cin >> q;
  while (q--) {
    int op, x, y, z;
    cin >> op >> x >> y;
    if (op == 2) {
      cin >> z;
      update(1, 1, n, x, y, z);
      continue;
    }
    cout << sum(1, 1, n, x, y) << "\n";
  }

  return 0;
}