将所有元素按照魔法值从大到小排序，然后依次试着往线性基里插入就完事了.
#include <cstdio>
#include <algorithm>
#define N 2000
#define M 62
#define ll long long
#define setIO(s) freopen(s".in","r",stdin)
using namespace std;
int n;
ll d[N];
struct Node
{
ll val,magic;
Node(ll val=0,ll magic=0):val(val),magic(magic){}
}e[N];
bool cmp(Node a,Node b)
{
return a.magic>b.magic;
}
int main()
{
ll re=0;
int i,j;
// setIO("input");
scanf("%d",&n);
for(i=1;i<=n;++i) scanf("%lld%lld",&e[i].val,&e[i].magic);
sort(e+1,e+1+n,cmp);
for(i=1;i<=n;++i)
{
ll x=e[i].val,y=e[i].magic;
for(j=M;j>=0;--j)
{
if(x&(1ll<<j))
{
if(d[j]) x^=d[j];
else
{
d[j]=x;
re+=y;
break;
}
}
}
}
printf("%lld
",re);
return 0;
}