#include<bits/stdc++.h>
#define Gc() getchar()
#define Me(x,y) memset(x,y,sizeof(x))
#define Mc(x,y) memcpy(x,y,sizeof(x))
#define d(x,y) ((m)*(x-1)+(y))
#define R(n) (rnd()%(n)+1)
#define Pc(x) putchar(x)
#define LB lower_bound
#define UB upper_bound
#define fi first
#define se second
#define eb emplace_back
#define all(x) x.begin(),x.end()
using namespace std;using ll=long long;using db=double;using lb=long db;using ui=unsigned;using ull=unsigned long long;using pii=pair<int,int>;
const int N=4e5+5,M=N*40+5,K=1000+5,mod=998244353,Mod=mod-1;const db eps=1e-9;const int INF=1e9+7;mt19937 rnd(28382);
#define Tp template<typename T>
#define Ts template<typename T,typename... Ar>
namespace Debug{
	Tp void _debug(char* f,T t){cerr<<f<<'='<<t<<endl;}
	Ts void _debug(char* f,T x,Ar... y){while(*f!=',') cerr<<*f++;cerr<<'='<<x<<",";_debug(f+1,y...);}
	#ifdef LOCAL
	#define gdb(...) _debug((char*)#__VA_ARGS__,__VA_ARGS__)
	#else 
	#define gdb(...) void()
	#endif
}using namespace Debug;
int n,m,A[N],L[N],ap[N];
struct ques{int l,r,ans,id;}Q[N];
const int Bl=512,k=9;
namespace Block{
	int bg,len;
	int A[Bl],B[Bl],ans,sum;
	int pt;
	int vis[Bl],id[Bl];
	short f[Bl],g[N];
	void work(short *g,int op){
		if(op){
			for(int i=k-2;~i;i--){
				for(int j=(1<<i);j<(1<<i+1);j++) g[j]=g[j+(1<<i)]^g[j+(2<<i)];
			}
		}else{
			for(int i=0;i<k-1;i++){
				for(int j=(1<<i);j<(1<<i+1);j++) g[j+(1<<i)]^=g[j],g[j+(2<<i)]^=g[j];
			}
		}
	}
	void push(){
		Me(f,0);
		for(int i=0;i<=pt;i++) f[Bl/2+(i&Bl/2-1)]^=g[i];
		for(int i=1;i<=pt;i++) g[i]^=g[i-1];
		for(int i=0;i<len;i++){
			int o=0;
			for(int j=Bl/2-1-(A[i]&Bl/2-1);;j+=Bl/2){
				if(g[min(j,pt)]^o) B[i]^=(A[i]+j>>k-1)<<k-1;
				if(j>pt) break;
				o=g[j];
			}
		}
		work(f,1);
		for(int i=1;i<k;i++){
			static int dp[Bl];
			copy(f+(1<<i),f+(1<<i+1),dp);
			int res=0;for(int j=(1<<i-1);j<(1<<i);j++) res^=dp[j];
			int R=(1<<i-1);
			for(int j=0;j<(1<<i);j++){
				f[j+(1<<i)]=res<<i-1;
				--R;if(R<0) R+=(1<<i);
				res^=dp[R]^dp[(1<<i)-1-j];
			}
		}
		f[1]=0;
		work(f,0);
		for(int i=0;i<len;i++) B[i]^=f[Bl/2+(A[i]&Bl/2-1)],A[i]+=pt;
		/*for(int i=0;i<len;i++){
			for(int j=0;j<=pt&&j<Bl/2;j++) if(f[j]) B[i]^=A[i]+j&Bl/2-1;
			A[i]+=pt;
		}*/
		fill(g,g+pt+1,0);pt=0;
	}
	void rebuild(){
		Me(vis,0);Me(id,-1);Me(f,0);
		for(int i=0;i<len;i++) vis[A[i]&Bl-1]^=1,id[A[i]&Bl-1]=A[i];
		for(int i=0;i<len;i++) f[Bl/2+(A[i]&Bl/2-1)]^=1;
		work(f,1);
		for(int i=0;i<k;i++){
			reverse(f+(1<<i)+1,f+(1<<i+1));
			for(int j=(1<<i);j<(1<<i+1);j++) f[j]<<=i;
		} 
		work(f,0);
	}
	void build(int l,int r){
		bg=l;len=r-l+1;ans=sum=0;
		Me(A,0);Me(B,0);fill(g,g+pt+1,0);pt=0;
		rebuild();
	}
	void add(){
		pt++;
		sum^=f[Bl/2+(pt&Bl/2-1)];
		int x=(Bl-(pt&Bl-1))&Bl-1;
		if(~id[x]&&vis[x]){
			int sw=((1<<__builtin_ctz(pt+id[x])+1)-1>>k)<<k;
			sum^=sw;
		}
		// for(int i=0;i<len;i++) sum^=(1<<__builtin_ctz(pt+A[i])+1)-1;
	}
	void add_range(int l,int r){
		l-=bg;r-=bg;push();
		for(int i=l;i<=r;i++) sum^=A[i],A[i]++,sum^=A[i];
		rebuild();
	}
	void modify(){
		ans^=sum;
		g[pt]^=1;
	}
	int qry(int l,int r){
		l-=bg;r-=bg;
		push();
		int res=0;
		for(int i=l;i<=r;i++) res^=B[i];
		rebuild();
		return res;
	}
}
void Solve(){
	scanf("%d%d",&n,&m);
	for(int i=1;i<=n;i++) scanf("%d",&A[i]);
	for(int i=1;i<=n;i++) L[i]=ap[A[i]]+1,ap[A[i]]=i;
	for(int i=1;i<=m;i++) scanf("%d%d",&Q[i].l,&Q[i].r),Q[i].id=i;
	sort(Q+1,Q+m+1,[](ques x,ques y){return x.r<y.r;});
	for(int l=1,r;l<=n;l=r+1){
		r=min(n,l+Bl-1);
		Block::build(l,r);
		int R=1;
		for(int j=1;j<=n;j++){
			if(L[j]<=l&&r<=j) Block::add();
			else if(L[j]<=r&&l<=j) Block::add_range(max(l,L[j]),min(r,j));
			Block::modify();
			while(R<=m&&Q[R].r==j){
				if(Q[R].l<=l&&r<=Q[R].r) Q[R].ans^=Block::ans;
				else if(Q[R].l<=r&&l<=Q[R].r) Q[R].ans^=Block::qry(max(l,Q[R].l),min(r,Q[R].r));
				R++;
			}
		}
	}
	sort(Q+1,Q+m+1,[](ques x,ques y){return x.id<y.id;});
	for(int i=1;i<=m;i++) printf("%d\n",Q[i].ans);
}
int main(){
	int t=1;
	// scanf("%d",&t);
	while(t--) Solve();
	cerr<<clock()*1.0/CLOCKS_PER_SEC<<'\n';
}