#include <bits/stdc++.h>
using namespace std;
#define rep(i,n) REP(i,0,n)
#define REP(i,s,e) for(int i=(s); i<(int)(e); i++)
#define repr(i, n) REPR(i, n, 0)
#define REPR(i, s, e) for(int i=(int)(s-1); i>=(int)(e); i--)
#define all(r) r.begin(),r.end()
#define rall(r) r.rbegin(),r.rend()

typedef long long ll;
typedef vector<int> vi;
typedef vector<ll> vl;

const ll INF = 1e18;
const ll MOD = 1e9 + 7;

template<typename T> T chmax(T& a, const T& b) { return a = (a > b ? a : b); }
template<typename T> T chmin(T& a, const T& b) { return a = (a < b ? a : b); }
void yes_no(bool f, string yes = "Yes", string no = "No") { cout << (f ? yes : no) << "\n"; }

#define DEBUG_MODE
#ifdef DEBUG_MODE
#define dump(x) cout << #x << " : " << x << " "
#define dumpL(x) cout << #x << " : " << x << '\n'
#define LINE cout << "line : " << __LINE__ << " "
#define LINEL cout << "line : " << __LINE__ << '\n'
#define dumpV(v) cout << #v << " : ["; for(auto& t : v) cout << t << ", "; cout<<"]" << " "
#define dumpVL(v) cout << #v << " : ["; for(auto& t : v) cout << t << ", "; cout<<"]" << endl
#define STOP assert(false)
#else
#define dump(x) 
#define dumpL(x) 
#define LINE 
#define LINEL 
#define dumpV(v) 
#define dumpVL(v) 
#define STOP assert(false)
#endif
#define mp make_pair

namespace std {
    template<class S, class T>
    ostream& operator <<(ostream& out, const pair<S, T>& a) {
        out << '(' << a.first << ", " << a.second << ')';
        return out;
    }
}

// hankaikukan
template<typename T>
struct RangeSet {
    using P = pair<T, T>;
    set<P> st;
    const T INF;
    const P NG;
    RangeSet() :INF(numeric_limits<T>::max() / 2), NG(P(INF, INF)) {}

    bool isIntersect(const T& x, const P& p) {
        return p.first <= x && x < p.second;
    }
    bool isIntersect(const P& p1, const P& p2) {
        if (p1.first < p2.first) return isIntersect(p2.first, p1);
        else return isIntersect(p1.first, p2);
    }
    bool isExist(const T& x) {
        auto it = st.lower_bound({ x, INF });
        if (it == st.begin()) return false;
        --it;
        return isIntersect(x, *it);
    }
    P get(const T& x) {
        if (!isExist(x)) return NG;
        auto it = st.lower_bound({ x, INF });
        --it;
        return *it;
    }
    P merge_range(const P& p1, const P& p2) {
        return P{ min(p1.first, p2.first), max(p1.second, p2.second) };
    }
    void add(const P& p) {
        P add = p;
        {
            auto tmp = get(p.first - 1);
            if (tmp != NG) {
                add = merge_range(add, tmp);
                st.erase(tmp);
            }
        }
        {
            auto tmp = get(p.first);
            if (tmp != NG) {
                add = merge_range(add, tmp);
                st.erase(tmp);
            }
        }
        {
            auto tmp = get(p.second);
            if (tmp != NG) {
                add = merge_range(add, tmp);
                st.erase(tmp);
            }
        }
        erase(add);
        st.insert(add);
    }
    void add(const T& x) {
        add(P{ x, x + 1 });
    }
    void erase(const P& p) {
        auto tmp = get(p.first);
        if (tmp == NG) return;
        auto it = st.find(tmp);
        while (it != st.end() && isIntersect(p, *it)) {
            auto erase_p = *it;
            if (erase_p.first < p.first) st.emplace(erase_p.first, p.first);
            if (p.second < erase_p.second) st.emplace(p.second, erase_p.second);
            st.erase(erase_p);
            it = st.upper_bound(erase_p);
        }
    }
    void erase(const T& x) {
        erase({ x, x + 1 });
    }
};

int main() {
    cin.tie(0);
    ios::sync_with_stdio(false);
    ll d, q;
    cin >> d >> q;
    RangeSet<ll> rs;
    ll ans = 0;
    rep(_, q) {
        ll a, b;
        cin >> a >> b;
        rs.add({ a, b + 1 });
        auto p = rs.get(a);
        chmax(ans, p.second - p.first);
        cout << ans << '\n';
    }

    return 0;
}