- More info on Gaussian Elimination technique in GF[2]: https://codeforces.com/blog/entry/68953
- Finding basis vectors for xor.
ll basis[32];
int basis_size=0;
void insert_vector(ll v){
for(int bit=0; bit<32; bit++){
ll msk = 1ll << bit;
if(v & msk){
if(!basis[bit]){
basis[bit] = v;
++basis_size;
return;
}
v ^= basis[bit];
}
}
}