 # How to use lazy propagation on segment tree in case of node's value is updating via XOR?

The problem is to update the elements of the range [L, R] via XOR- ing each of them with the given X.
In the case of just a normal segment tree, we can use lazy propagation to calculate the parent node sum value just in this way:

`(end - start + 1) * val`

And the whole code for an update, in this case, could be like as shown below:

``````void updateRange(int node, int start, int end, int l, int r, int val)
{
if(lazy[node] != 0)
{
tree[node] += (end - start + 1) * lazy[node];
if(start != end)
{
lazy[node*2] += lazy[node];
lazy[node*2+1] += lazy[node];
}
lazy[node] = 0;
}
if(start > end or start > r or end < l)
return;
if(start >= l and end <= r)
{
tree[node] += (end - start + 1) * val;
if(start != end)
{
lazy[node*2] += val;
lazy[node*2+1] += val;
}
return;
}
int mid = (start + end) / 2;
updateRange(node*2, start, mid, l, r, val);
updateRange(node*2 + 1, mid + 1, end, l, r, val);
tree[node] = tree[node*2] + tree[node*2+1];
}
``````

But the problem in the case of XOR is that we can’t write something like (end - start + 1) * val for the parent node?
So which techniques could be applied in such a case?