#define _USE_MATH_DEFINES
#pragma region include
#include <iostream>
#include <iomanip>
#include <stdio.h>

#include <sstream>
#include <algorithm>
#include <iterator>
#include <cmath>
#include <complex>

#include <string>
#include <cstring>
#include <vector>
#include <bitset>

#include <queue>
#include <set>
#include <map>
#include <stack>
#include <list>

#include <ctime>
////
//#include <random>//
#pragma endregion //#include
/////////

#pragma region typedef
typedef long long LL;
typedef long double LD;
typedef unsigned long long ULL;
#pragma endregion //typedef
////定数
const int INF = (int)1e9;
const LL MOD = (LL)1e9+7;
const LL LINF = (LL)4e18+20;
const LD PI = acos(-1.0);
const double EPS = 1e-9;
/////////
using namespace::std;

void solve(){
	LL D,Q;
	cin>>D>>Q;
	vector<vector<LL> > seq;
	vector<LL> dat(2);
	dat[0] = 0;
	dat[1] = D-1;
	seq.push_back( dat );
	vector<LL> sya(2);
	while(Q--){
		cin>>sya[0]>>sya[1];
		int size = seq.size();
		vector<vector<LL> >next;
		LL ans = 0;
		for(int i=0;i<size;++i){
			dat = seq[i];
			if( sya[1] < dat[0] || dat[1] < sya[0]){
				next.push_back( dat );
			}else if( sya[0]<=dat[0] && dat[1]<=sya[1]){
				//丸つぶれ
			}else if(dat[0]<sya[0] && sya[1]<dat[1] ){
				//中にある。
				vector<LL> temp(2);
				temp[0] = dat[0];
				temp[1] = sya[0]-1;
				next.push_back( temp );
				temp[0] = sya[1]+1;
				temp[1] = dat[1];
				next.push_back( temp );
			}else if(dat[0] <= sya[1] ){
				vector<LL> temp(2);
				temp[0] = sya[1]+1;
				temp[1] = dat[1];
				next.push_back( temp );
			}else if(sya[0]<=dat[1] ){
				vector<LL> temp(2);
				temp[0] = dat[0];
				temp[1] = sya[0]-1;
				next.push_back( temp );
			}
		}
		seq = next;
		size = seq.size();
		ans = 0;
		if(size==0){
			ans = D;
		}
		for(int i=0;i<size;++i){
			if( i-1 >= 0 ){//一個前がある
				LL res = seq[i][0]-seq[i-1][1]-1;
				ans = max(ans,res);
			}else{
				LL res = seq[i][0]-0;
				ans = max(ans,res);
			}
			if(i+1 < size ){//一個次がある。
				LL res = seq[i+1][0]-seq[i][1]-1;
				ans = max(ans,res);
			}else{
				LL res = D-1 - seq[i][1];
				ans = max(ans,res);
			}
		}
		cout << ans << endl;
	}
}

#pragma region main
signed main(void){
	std::cin.tie(0);
	std::ios::sync_with_stdio(false);
	std::cout << std::fixed;//小数を10進数表示
	cout << setprecision(16);//小数点以下の桁数を指定//coutとcerrで別	

	solve();
}
#pragma endregion //main()