线性基求交板子

Posted 2022-05-22 uid001

    _ operator + (const _ &rhs) const 
        _ ret;
        unsigned p[32], f[32];
        REP(i,0,31) p[i] = a[i];
        PER(i,0,31) 
            auto x = rhs.a[i], y = 1u<<i;
            PER(j,0,31) if (x>>j&1) 
                if (p[j]) x^=p[j],y^=f[j];
                else 
                    p[j]=x,f[j]=y;
                    break;
                
            
            if (x==0) 
                unsigned sum = 0;
                REP(j,0,31) if (y>>j&1) sum ^= rhs.a[j];
                ret.ins(sum);
            
        
        return ret;