【BZOJ3261】最大异或和（可持久化Trie）

题意：

思路：可持久化Trie板子题，支持序列插入和询问

 #include<bits/stdc++.h>
 using namespace std;
 typedef long long ll;
 typedef unsigned int uint;
 typedef unsigned long long ull;
 typedef long double ld;
 typedef pair<int,int> PII;
 typedef pair<ll,ll> Pll;
 typedef vector<int> VI;
 typedef vector<PII> VII;
 typedef pair<ll,ll>P;
 #define N  12000010
 #define M  6000010
 #define INF 1e9
 #define fi first
 #define se second
 #define MP make_pair
 #define pb push_back
 #define pi acos(-1)
 #define mem(a,b) memset(a,b,sizeof(a))
 #define rep(i,a,b) for(int i=(int)a;i<=(int)b;i++)
 #define per(i,a,b) for(int i=(int)a;i>=(int)b;i--)
 #define lowbit(x) x&(-x)
 #define Rand (rand()*(1<<16)+rand())
 #define id(x) ((x)<=B?(x):m-n/(x)+1)
 #define ls p<<1
 #define rs p<<1|1
 #define fors(i) for(auto i:e[x]) if(i!=p)

 const int MOD=1e8+,inv2=(MOD+)/;
       int p=1e4+;
       double eps=1e-;
       int dx[]={-,,,};
       int dy[]={,,-,};

 char ch[];
 int t[N][],s[N],root[N],b[N],cnt;

 int read()
 {
    int v=,f=;
    char c=getchar();
    while(c<||<c) {if(c=='-') f=-; c=getchar();}
    while(<=c&&c<=) v=(v<<)+v+v+c-,c=getchar();
    return v*f;
 }

 ll readll()
 {
    ll v=,f=;
    char c=getchar();
    while(c<||<c) {if(c=='-') f=-; c=getchar();}
    while(<=c&&c<=) v=(v<<)+v+v+c-,c=getchar();
    return v*f;
 }

 void ins(int p1,int &p2,int z,int d)
 {
     int p=(z>>d)&;
     p2=++cnt;
     s[p2]=s[p1]+;
     if(d<) return;
     t[p2][p^]=t[p1][p^];
     ins(t[p1][p],t[p2][p],z,d-);
 }

 int query(int p1,int p2,int z,int d)
 {
     if(d<) return ;
     int p=(z>>d)&;
     if(s[t[p2][p^]]-s[t[p1][p^]]) return (<<d)+query(t[p1][p^],t[p2][p^],z,d-);
      else return query(t[p1][p],t[p2][p],z,d-);
 }

 int main()
 {
     //freopen("1.in","r",stdin);
     //freopen("1.out","w",stdout);
     cnt=;
     ins(,root[],,);
     int n=read(),m=read();
     n++;
     rep(i,,n)
     {
         int x=read();
         b[i]=b[i-]^x;
         ins(root[i-],root[i],b[i],);
     }
     while(m--)
     {
         scanf("%s",ch);
         if(ch[]=='A')
         {
             int x=read();
             n++;
             b[n]=b[n-]^x;
             ins(root[n-],root[n],b[n],);
         }
          else
          {
              int l=read(),r=read(),x=read();
              int ans=query(root[l-],root[r],b[n]^x,);
              printf("%d\n",ans);
          }
     }

     return ;
 }