BZOJ 5495: [2019省队联测]异或粽子 可持久化trie+堆

和超级钢琴，异或之三倍经验 $?$ 

堆+贪心素质三连 $?$  

好无聊......

code: 

#include <bits/stdc++.h>    
#define N 500006   
#define ll long long 
#define setIO(s) freopen(s".in","r",stdin)  // , freopen(s".out","w",stdout)   
using namespace std;
char buf[100000],*p1,*p2;
#define nc() (p1==p2&&(p2=(p1=buf)+fread(buf,1,100000,stdin),p1==p2)?EOF:*p1++)
ll rd()
{
    ll x=0; char s=nc();
    while(s<'0') s=nc();
    while(s>='0') x=(ll)(((x<<2)+x)<<1)+s-'0',s=nc();
    return x;
}                   
namespace trie 
{      
    int tot; 
    int cnt[N*42],ch[N*42][2];     
    int newnode() { return ++tot; }     
    void Insert(int pre,int &x,ll v) 
    { 
        int now=x=newnode(),i; 
        for(i=40;i>=0;--i) 
        {
            int o=(1ll*(v>>i)&1);     
            ch[now][o^1]=ch[pre][o^1]; 
            ch[now][o]=newnode();  
            pre=ch[pre][o]; 
            now=ch[now][o];   
            cnt[now]=cnt[pre]+1;  
        }
    }   
    ll query(int x,int y,ll z)      
    {
        ll re=0; 
        int i;  
        for(i=40;i>=0;--i)     
        {
            int o=(1ll*(z>>i)&1);   
            if(ch[x][o^1]<ch[y][o^1])   re+=(1ll<<i),x=ch[x][o^1],y=ch[y][o^1]; 
            else x=ch[x][o],y=ch[y][o];           
        }       
        return re;  
    }         
}; 
struct node 
{
    int o,l,r; 
    ll val;  
    int pos;      
    node(int a=0,int b=0,int c=0,ll d=0,int e=0):o(a),l(b),r(c),val(d),pos(e){}   
    bool operator<(node b) const 
    {
        return b.val>val; 
    }
}; 
priority_queue<node>q;     
ll A[N],ar[N],id[N];   
int rt[N];        
set<int>S[N];  
set<int>::iterator it;   
int main() 
{ 
    // setIO("input");  
    int i,j,n,k,ou=0; 
    n=rd(),k=rd();                  
    for(i=1;i<=n;++i)   
    {
        A[i]=rd()^A[i-1];     
        id[i]=ar[i]=A[i];                     
        trie::Insert(rt[i-1],rt[i],A[i]);       
    }           
    sort(ar+1,ar+1+n);   
    for(i=1;i<=n;++i)    id[i]=lower_bound(ar+1,ar+1+n,id[i])-ar;          
    for(i=1;i<=n;++i)    S[(int)id[i]].insert(i);   
    for(i=0;i<n;++i) 
    {   
        int l=i+1,r=n;  
        ll tmp=trie::query(rt[l-1],rt[r],A[i]);              
        int idx=lower_bound(ar+1,ar+1+n,A[i]^tmp)-ar;              
        int pos=*S[idx].lower_bound(l);         
        q.push(node(i,l,r,tmp,pos));               
    }    
    ll ans=0ll;   
    while(ou<k) 
    {
        node e=q.top(); q.pop();   
        ans+=(ll)e.val,++ou;                                          
        int pos=e.pos;                        
        if(pos!=e.l)                 
        {   
            ll tmp=trie::query(rt[e.l-1],rt[pos-1],A[e.o]);   
            int idx=lower_bound(ar+1,ar+1+n,A[e.o]^tmp)-ar;           
            int t=*S[idx].lower_bound(e.l); 
            q.push(node(e.o,e.l,pos-1,tmp,t));   
        }
        if(pos!=e.r)  
        {
            ll tmp=trie::query(rt[pos],rt[e.r],A[e.o]);  
            int idx=lower_bound(ar+1,ar+1+n,A[e.o]^tmp)-ar;       
            int t=*S[idx].lower_bound(pos+1);                  
            q.push(node(e.o,pos+1,e.r,tmp,t));      
        }
    }
    printf("%lld
",ans);  
    return 0; 
}