#include <bits/stdc++.h>
using namespace std;
//#include <atcoder/all>
//using namespace atcoder;
using ll = long long;
using vll = vector<ll>;
using vvll = vector<vll>;
using vvvll = vector<vvll>;
using vvvvll = vector<vvvll>;
using vvvvvll = vector<vvvvll>;
using vvvvvvll = vector<vvvvvll>;
using vb = vector<bool>;
using vvb = vector<vb>;
using vvvb = vector<vvb>;
using vvvvb = vector<vvvb>;
using vd = vector<double>;
using vvd = vector<vd>;
using vvvd = vector<vvd>;
using vvvvd = vector<vvvd>;
using vvvvvd = vector<vvvvd>;
#define all(A) A.begin(),A.end()
#define ALL(A) A.begin(),A.end()
#define rep(i, n) for (ll i = 0; i < (ll) (n); i++)
using pqr = priority_queue<pair<ll, ll>, vector<pair<ll, ll>>, greater<pair<ll, ll>>>;
#define tN(t) (t==1?XN:YN)
#define tS(t) (t==1?XS:YS)
#define tA(t) (t==1?XA:YA)

template<class T>
bool chmax(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p < q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}

template<class T>
bool chmin(T& p, T q, bool C = 1) {
    if (C == 0 && p == q) {
        return 1;
    }
    if (p > q) {
        p = q;
        return 1;
    }
    else {
        return 0;
    }
}

ll gcd(ll(a), ll(b)) {
    if (b == 0)return a;
    ll c = a;
    while (a % b != 0) {
        c = a % b;
        a = b;
        b = c;
    }
    return b;
}
ll sqrtz(ll N) {
    ll L = 0;
    ll R = sqrt(N) + 10000;
    while (abs(R - L) > 1) {
        ll mid = (R + L) / 2;
        if (mid * mid <= N)L = mid;
        else R = mid;
    }
    return L;

}


/*
区間をsetで管理するテク
区間は半開区間で持たせる[L,R)
*/
template<class T>
struct rangeset{
    set<pair<T,T>> S;
    T INF;
    rangeset(){
        INF=2e18;;
        S.insert({INF,INF});
        S.insert({-INF,-INF});
    }
    bool iscovered(T L,T R){
        //assert(L<=R);
        auto itr=S.lower_bound({L+1,L+1});
        itr=prev(itr);
        auto st=*itr;
        return (itr->first<=L&&R<=itr->second);
    }
    bool iscovered(T x){
        return iscovered(x,x+1);
    }
    pair<T,T> covered(T L,T R){
        //assert(L<=R);
        auto itr=S.lower_bound({L+1,L+1});
        itr--;
        auto st=*itr;
        if(itr->first<=L&&R<=itr->second){
            return st;
        }
        else{
            return {INF,INF};
        }
    }
    pair<T,T> covered(T x){
        return covered(x,x+1);
    }
    T insert(T L,T R){
        if(iscovered(L,R))return T(0);
        auto itr=S.lower_bound({L+1,L+1});
        itr=prev(itr);
        T res=T(0);
        auto st=*itr;
        if(itr->first<=L&&L<=itr->second){
            L=st.first;
            res-=itr->second-itr->first;
            itr=S.erase(itr);
        }
        else itr=next(itr);
        while(R>itr->second){
            res-=itr->second-itr->first;
            itr=S.erase(itr);
        }
        if(itr->first<=R&&R<=itr->second){
            res-=itr->second-itr->first;
            R=itr->second;
            itr=S.erase(itr);
        }
        S.insert({L,R});
        res+=R-L;
        return res;
    }
    T insert(T x){
        return insert(x,x+1);
    }

    T erase(T L,T R){
        auto itr=S.lower_bound({L+1,L+1});
        itr=prev(itr);
        T res=T(0);
        auto st=*itr;
        if(itr->first<=L&&R<=itr->second){
            if(itr->first<L)S.insert({itr->first,L});
            if(R<itr->second)S.insert({R,itr->second});
            S.erase(itr);
            return R-L;
        }
        if(itr->first<=L&&L<itr->second){
            res+=itr->second-L;
            if(itr->first<L)S.insert({itr->first,L});
            itr=S.erase(itr);
        }
        else itr=next(itr);

        while(itr->second<=R){
            res+=itr->second-itr->first;
            itr=S.erase(itr);
        }

        if(itr->first<R&&R<=itr->second){
            res+=R-itr->first;
            if(R<itr->second)S.insert({R,itr->second});
            S.erase(itr);
        }
        return res;
    }
    T erase(T x){
        return erase(x,x+1);
    }
};




int main() {
    cin.tie(nullptr);
    ios::sync_with_stdio(false);

    rangeset<ll> S;

    ll N,Q;
    cin>>N>>Q;
    ll an=0;
    rep(i,Q){
        ll A,B;
        cin>>A>>B;
        S.insert(A,B+1);
        auto p=S.covered(A);
        chmax(an,p.second-p.first);
        cout<<an<<endl;
    }
    
    
}