/**************************************************************

     Problem: 3261

     User: Tunix

     Language: C++

     Result: Accepted

     Time:3888 ms

     Memory:239552 kb

 ****************************************************************/

 //BZOJ 3261

 #include<cstdio>

 #include<cstring>

 #include<cstdlib>

 #include<iostream>

 #include<algorithm>

 #define rep(i,n) for(int i=0;i<n;++i)

 #define F(i,j,n) for(int i=j;i<=n;++i)

 #define D(i,j,n) for(int i=j;i>=n;--i)

 #define pb push_back

 using namespace std;

 typedef long long LL;

 inline int getint(){

     int r=,v=; char ch=getchar();

     for(;!isdigit(ch);ch=getchar()) if (ch=='-') r=-;

     for(; isdigit(ch);ch=getchar()) v=v*-''+ch;

     return r*v;

 }

 const int N=;

 /*******************template********************/

 int n,m,t[N][],tot,rt[],id[N];

 inline void Ins(int pre,int x,int k){

     int now=rt[k]=++tot; id[tot]=k;

     D(i,,){

         int j=(x>>i)&;

         t[now][j^]=t[pre][j^];

         t[now][j]=++tot; id[tot]=k; now=tot;

         pre=t[pre][j];

     }

 }

 inline int ask(int l,int r,int x){

     int ans=,now=rt[r];

     D(i,,){

         int j=((x>>i)&)^;

         if (id[t[now][j]]>=l) ans|=<<i; else j^=;

         now=t[now][j];

     }

     return ans;

 }

 int main(){

 #ifndef ONLINE_JUDGE

     freopen("3261.in","r",stdin);

     freopen("3261.out","w",stdout);

 #endif

     n=getint(); m=getint();

     id[]=-;

     Ins(rt[],,);

     int sum=;

     F(i,,n){

         sum^=getint();

         Ins(rt[i-],sum,i);

     }

     char cmd[]; int x,l,r;

     F(i,,m){

         scanf("%s",cmd);

         if (cmd[]=='A'){

             sum^=getint();

             Ins(rt[n],sum,n+); n++;

         }else{

             l=getint(); r=getint(); x=getint();

             printf("%d\n",ask(l-,r-,sum^x));

         }

     }

     return ;

 }