#include <bits/stdc++.h>
using namespace std;

const int N=100050;
int l,n;
int a[N],x[N];
int L[N],R[N];

int maxSteps,steps;

bool Check(int mn,int mx,bool reconstruct=false){
	x[0]=0;x[n]=l;
	L[0]=R[0]=0;
	a[n+1]=l;
	for(int i=1;i<=n;i++){
		L[i]=max(L[i-1]+mn,a[i]);
		R[i]=min(R[i-1]+mx,a[i+1]);
		if(L[i]>R[i])return false;
	}
	if(R[n]<l)return false;
	if(reconstruct){
		//for(int i=1;i<=n;i++){
		//	printf("L:%i R:%i\n",L[i],R[i]);
		//}
		for(int i=n-1;i>=1;i--){
			x[i]=max(L[i],x[i+1]-mx);
		}
	}
	return true;
}

int Get(int mn,bool reconstruct=false){
	int top=l,bot=mn,ans=l;
	while(top>=bot){
		int mid=top+bot>>1;
		if(Check(mn,mid)){
			top=mid-1;
			ans=mid;
		}else{
			bot=mid+1;
		}
	}
	if(reconstruct){
		Check(mn,ans,true);
	}
	return ans-mn;
}

int Find(){
	int top=l/n,bot=1,ans=1;
	while(top>=bot){
		int mid=top+bot>>1;
		if(Check(mid,l)){
			bot=mid+1;
			ans=mid;
		}else{
			top=mid-1;
		}
	}
	return ans;
}

void Solve(){
	int bot=1;
	int ans=Find();
	int top=ans-1;
	while(top>=bot){
		int mid=top+bot>>1;
		int best1=Get(mid);
		int best2=Get(mid+1);
		if(best2<best1){
			bot=mid+1;
		}else{
			top=mid-1;
			ans=mid;
		}
	}
	//printf("mn:%i diff:%i\n",ans,Get(ans));
	Get(ans,true);


	/*x[0]=0;x[n]=l;
	for(int i=1;i<n;i++){
		x[i]=a[i];
	}
	steps=0;
	while(true){
		steps++;
		bool change=false;
		for(int i=n-1;i>=1;i--){
			int newX=max(a[i],min(a[i+1],(x[i-1]+x[i+1])/2));
			if(newX!=x[i])change=true;
		}
		if(!change)break;
	}
	maxSteps=max(maxSteps,steps);*/
}

const int mxn=1e5;
const int mxl=1e9;

mt19937 rng(time(0));
void Gen(){
	n=rng()%mxn+1;
	l=rng()%(mxl-n-1)+n+1;
	set<int> used;
	auto Bad=[&](int x){
		return x<=0 || x>=l || used.count(x);
	};
	for(int i=1;i<=n;i++){
		a[i]=rng()%(l-1)+1;
		int j=0;
		while(Bad(a[i]+j) && Bad(a[i]-j)){
			j++;
		}
		if(Bad(a[i]+j))a[i]-=j;
		else a[i]+=j;
		used.insert(a[i]);
	}
	sort(a+1,a+1+n);
}

const int tests=1e3;
void Test(){
	for(int test=0;test<tests;test++){
		Gen();
		printf("generated test %i\n",test);
		Solve();
		printf("test %i: %i\n",test,steps);
	}
	printf("%i\n",maxSteps);
}

int main(){
	//Test();
	scanf("%i %i",&l,&n);
	for(int i=1;i<=n;i++)scanf("%i",&a[i]);
	Solve();
	for(int i=1;i<=n;i++)printf("%i %i\n",x[i-1],x[i]);
	return 0;
}