#include<bits/stdc++.h>
#define For(i,a,b) for( int i=(a);i<=(b);++i)
#define Rep(i,a,b) for( int i=(a);i>=(b);--i)
using namespace std;
inline int read()
{
	char c=getchar();int x=0;bool f=0;
	for(;!isdigit(c);c=getchar())f^=!(c^45);
	for(;isdigit(c);c=getchar())x=(x<<1)+(x<<3)+(c^48);
	if(f)x=-x;return x;
}

#define fi first
#define se second
#define pb push_back
#define mkp make_pair
typedef pair<int,int>pii;
typedef vector<int>vi;

#define maxn 400005
#define inf 0x3f3f3f3f

int n,m,t,col[maxn],pre[maxn],nl[maxn],res[maxn];
vector<pii>q[maxn];

#define B 512
#define S 511
int rev[B<<1|5],dep[B<<1|5];
int a[B+5],his[B+5],add,sum[2],f[B+5],lstsum,now;
int cnt[B<<1|5],tr[B<<1|5];
int addc[2][B+5],addv[2][B+5],av[B+5],al[B+5];

int g[B<<1|5];
void trans(int*f){
	For(i,0,B-1)cnt[rev[i]|B]=f[i]&1;
	Rep(i,B-1,1)cnt[i]=cnt[i<<1]^cnt[i<<1|1];
	For(i,1,B|S)tr[i]=tr[i>>1]^(cnt[i]<<dep[i]);
	For(i,0,B-1)f[i]=tr[rev[i]|B];
}

void clear(){
	sum[0]=sum[1]=0;
	memset(f,0,sizeof f);
	memset(addc,0,sizeof addc);
	memset(addv,0,sizeof addv);
	memset(av,-1,sizeof av);
}

int lstt=0,o;

void down(){
//	cout<<"down\n"; 
	if(add){
		trans(addc[o]);
		For(i,1,B){
			int c=(a[i]&S);
			his[i]^=addc[o][c]^addv[o][c];
			a[i]+=add;
		}
	}else{
		if(o==lstt)
			For(i,1,B)his[i]^=a[i];
	}
	add=0;
}

void rebuild(){
	clear();
	for(int l=1,r;l<=B;l=r+1){
		r=l; while(r<B&&a[r+1]==a[l])++r;
		int c=(a[l]&S);
		av[c]=a[l],f[c]=al[c]=(r-l+1&1);
		if(al[c])sum[o^1]^=a[l];
		addv[o^1][c]=a[l];
	}
	trans(f);
	lstt=o^1;
}

void mdf(int l,int r){
	l=max(l,1),r=min(r,B);
	down();
	++t; o^=1; lstsum=0;
	For(i,l,r)++a[i];
	For(i,1,B)his[i]^=a[i],lstsum^=his[i]; 
	rebuild();
}

void addone(){
	int c=(S^(add&S));
	++add;
	++t; o^=1;
	sum[o]^=f[c];
	addc[o][c]^=1;
	if(av[c]!=-1){
		int val=(av[c]+add)^(av[c]+add-1)^B^S;
		if(al[c]) sum[o]^=val;
		addv[o][c]^=val;
	}
}

int ask(int l,int r){
	l=max(l,1),r=min(r,B);
	int res=0;
	if(add){
		down();
		lstsum=0;
		For(i,1,B)lstsum^=his[i];
		For(i,l,r)res^=his[i];
		rebuild();
		return res;
	}
	For(i,l,r)res^=his[i]^addv[o][a[i]&S];
	return res;
}

signed main()
{
//	freopen("data.in","r",stdin);
//	freopen("now.out","w",stdout);
	n=read(),m=read();
	For(i,0,B-1)rev[i]=(rev[i>>1]>>1)|((i&1)*(B>>1));
	For(i,2,B*2-1)dep[i]=dep[i>>1]+1;
	For(i,1,n)col[i]=read();
	For(i,1,m){
		int l=read(),r=read();
		q[r].pb(mkp(l,i));
	}
	For(i,1,n)nl[i]=pre[col[i]]+1,pre[col[i]]=i;
	For(_,1,(n-1)/B+1){
		
		int L=(_-1)*B+1,R=L+B-1;
		memset(a,0,sizeof a);
		memset(his,0,sizeof his);
		add=lstsum=now=0;
		clear();
		av[0]=0,al[0]=0;
		
		t=0;o=0;
		For(i,L,n){
			int tl=nl[i],tr=i,ttr=tr-L+1;
			if(tl<=L&&tr>=R) addone();
			else if(tl<=R)mdf(tl-L+1,ttr);
			else ++t,o^=1;
			
			int nowsum=lstsum^sum[o];
			for(auto t:q[i]){
				tl=t.fi;
				if(tl<=L&&tr>=R) res[t.se]^=nowsum;
				else if(tl<=R) res[t.se]^=ask(tl-L+1,ttr);
			}
		}
	}
	For(i,1,m)printf("%d\n",res[i]);
	return 0;
}