#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define repp(i,a,b) for(int i=(a);i>=(b);--i)
#define ll long long
#define see(x) (cerr<<(#x)<<'='<<(x)<<endl)
#define inf 0x3f3f3f3f
#define CLR(A,v)  memset(A,v,sizeof A)
//
const int N=2e6+10;
int t[N<<5][2],Lmax[N<<5],ncnt,n,m,x,y,z,T[N],s[N];
char ss[2];
void upnode(int k,int i,int pre,int pos)
{if(k<0){Lmax[pos]=i;return ;}bool c=(s[i]>>k)&1;if(pre)t[pos][c^1]=t[pre][c^1];t[pos][c]=++ncnt;upnode(k-1,i,t[pre][c],t[pos][c]);Lmax[pos]=max(Lmax[t[pos][0]],Lmax[t[pos][1]]);
}
int qmax(int k,int val,int l,int pos)
{if(k<0)return val^s[Lmax[pos]];bool c=(val>>k)&1;if(Lmax[t[pos][c^1]]>=l)return qmax(k-1,val,l,t[pos][c^1]);else return qmax(k-1,val,l,t[pos][c]);
}
int main()
{scanf("%d%d",&n,&m);Lmax[0]=-1;T[0]=++ncnt;upnode(23,0,0,T[0]);rep(i,1,n){int x;scanf("%d",&x);s[i]=s[i-1]^x;T[i]=++ncnt;upnode(23,i,T[i-1],T[i]);}int l,r;while(m--){scanf("%s",ss);if(ss[0]=='A'){    int x;scanf("%d",&x);n++;s[n]=s[n-1]^x;T[n]=++ncnt;upnode(23,n,T[n-1],T[n]);}else {scanf("%d%d%d",&l,&r,&x);int val=x^s[n];printf("%d\n",qmax(23,val,l-1,T[r-1]));}}return 0;
}

#include<bits/stdc++.h>
using namespace std;
#define rep(i,a,b) for(int i=(a);i<=(b);i++)
#define repp(i,a,b) for(int i=(a);i>=(b);--i)
#define ll long long
#define see(x) (cerr<<(#x)<<'='<<(x)<<endl)
#define inf 0x3f3f3f3f
#define CLR(A,v)  memset(A,v,sizeof A)
//
const int N=2e6+10;
int t[N<<5][2],ncnt,n,m,x,y,z,T[N],s[N],siz[N<<5];
char ss[2];
void upnode(int k,int val,int pre,int &pos)
{pos=++ncnt;t[pos][0]=t[pre][0];t[pos][1]=t[pre][1];siz[pos]=siz[pre]+1;if(k<0)return ;int c=(val>>k)&1;upnode(k-1,val,t[pre][c],t[pos][c]);
}
int qmax(int k,int val,int pre,int pos)
{if(k<0)return 0;int c=(val>>k)&1;int si=siz[t[pos][c^1]]-siz[t[pre][c^1]];if(si)return (1<<k)+qmax(k-1,val,t[pre][c^1],t[pos][c^1]);else return qmax(k-1,val,t[pre][c],t[pos][c]);
}
int main()
{scanf("%d%d",&n,&m);upnode(23,0,0,T[0]);rep(i,1,n){int x;scanf("%d",&x);s[i]=s[i-1]^x;upnode(23,s[i],T[i-1],T[i]);}int l,r; while(m--){scanf("%s",ss);if(ss[0]=='A'){    int x;scanf("%d",&x);n++;s[n]=s[n-1]^x;upnode(23,s[n],T[n-1],T[n]);}else {scanf("%d%d%d",&l,&r,&x);int val=x^s[n];printf("%d\n",qmax(23,val,T[l-2],T[r-1]));}}return 0;
}