bzoj2640 元素 线性基+贪心

#include <cstdio>
#include <cstring>
#include <cstdlib>
#include <iostream>
#include <algorithm>
#define ll long long
#define mem(a,b) memset(a,b,sizeof(a))
using namespace std;
const int N=1006;

struct JI
{
    ll order;
    ll val;
    bool friend operator < (JI a,JI b)
    {
        return a.val>b.val;
    }
}ji[N];

ll n;
ll p[68];

ll work()
{
    ll ans=0;
    sort(ji+1,ji+1+n);
    for(int i=1;i<=n;++i)
    {
        for(int j=62;j>=0;--j)
            if( (((ll)1<<j)&ji[i].order) )
            {
                if(!p[j])
                {
                    p[j]=ji[i].order;
                    break;
                }
                ji[i].order^=p[j];
            }
        if(ji[i].order)
            ans+=ji[i].val;
    }
    return ans;
}

int main(){
    
    //freopen("in.in","r",stdin);

    scanf("%lld",&n);
    for(int i=1;i<=n;++i)
        scanf("%lld%lld",&ji[i].order,&ji[i].val);
    cout<<work();
}