bzoj 2460 [BeiJing2011]元素 (线性基）

#include<bits/stdc++.h>
using namespace std;
#define ll long long
const int M = 1e6+10;
struct Linear_Basis{
    ll b[63],nb[63],tot;
    void init(){
        tot = 0;
        memset(b,0,sizeof(b));
        memset(nb,0,sizeof(nb));
    }

    bool Insert(ll x){
        for(int i = 62;i >= 0;i --){
            if(x&(1LL<<i)){
                if(!b[i]){
                    b[i] = x;
                    break;
                }
                x ^= b[i];
            }
        }
        return x > 0;
    }

    ll Max(ll x){
        ll ret = x;
        for(int i = 62;i >= 0;i --)
            ret = max(ret,ret^b[i]);
        return ret;
    }

    ll Min(ll x){
        ll ret = x;
        for(int i = 0;i <= 62;i ++)
            if(b[i]) ret ^= b[i];
        return ret;
    }

    void rebuild(){
        for(int i = 62;i >= 0;i --)
            for(int j = i-1;j >= 0;j --)
                if(b[i]&&(1LL<<j)) b[i]^=b[j];
        for(int i = 0;i <= 62;i ++)
            if(b[i]) nb[tot++] = b[i];
    }

    ll K_Min(ll k){
        ll res = 0;
        if(k >= (1LL<<tot))
            return -1;
        for(int i = 62;i >= 0;i --)
            if(k&&(1LL<<i))
                res ^= nb[i];
        return res;
    }
}LB;


struct node{
    ll a,b;
}p[M];

bool cmp(node x,node y){
    return x.b > y.b;
}

int main(){
    int n;
    while(scanf("%d",&n)!=EOF){
        LB.init();
        ll ans = 0;
        for(int i = 1;i <= n;i ++)
            scanf("%lld%lld",&p[i].a,&p[i].b);
        sort(p+1,p+1+n,cmp);
        for(int i = 1;i <= n;i ++){
            if(LB.Insert(p[i].a))
                ans += p[i].b;
        }
        printf("%lld\n",ans);
    }
}