#include <bits/stdc++.h>
#include <atcoder/all>
using namespace std;
using namespace atcoder;
istream &operator>>(istream &is, modint &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint &a) { return os << a.val(); }
istream &operator>>(istream &is, modint998244353 &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint998244353 &a) { return os << a.val(); }
istream &operator>>(istream &is, modint1000000007 &a) { long long v; is >> v; a = v; return is; }
ostream &operator<<(ostream &os, const modint1000000007 &a) { return os << a.val(); } 

typedef long long ll;
typedef vector<vector<int>> Graph;
typedef pair<int, int> pii;
typedef pair<ll, ll> pll;
#define FOR(i,l,r) for (int i = l;i < (int)(r); i++)
#define rep(i,n) for (int i = 0;i < (int)(n); i++)
#define all(x) x.begin(), x.end()
#define rall(x) x.rbegin(), x.rend()
#define my_sort(x) sort(x.begin(), x.end())
#define my_max(x) *max_element(all(x))
#define my_min(x) *min_element(all(x))
template<class T> inline bool chmax(T& a, T b) { if (a < b) { a = b; return 1; } return 0; }
template<class T> inline bool chmin(T& a, T b) { if (a > b) { a = b; return 1; } return 0; }
const int INF = (1<<30) - 1;
const ll LINF = (1LL<<62) - 1;
const int MOD = 998244353;
const int MOD2 = 1e9+7;
const double PI = acos(-1);
vector<int> di = {1,0,-1,0};
vector<int> dj = {0,1,0,-1};

#ifdef LOCAL
#  include <debug_print.hpp>
#  define debug(...) debug_print::multi_print(#__VA_ARGS__, __VA_ARGS__)
#else
#  define debug(...) (static_cast<void>(0))
#endif

// https://atcoder.jp/contests/abc330/editorial/7754
template <class T>
struct range_set {
    private:
        const T TINF = std::numeric_limits<T>::max() / 2;
        T sum;
        std::set<std::pair<T, T>> st;
    public:
        range_set() : sum(0) {
            st.emplace(-TINF, -TINF);
            st.emplace(TINF, TINF);
        }
        //[l, r) is covered?
        bool covered(const T l, const T r) {
            assert(l <= r);
            if(l == r) return true;
            auto itr = prev(st.upper_bound({l, TINF}));
            return itr->first <= l and r <= itr->second;
        }
        //[x, x + 1) is covered?
        bool covered(const T x) { return covered(x, x + 1); }
        // return section which covers[l, r)
        // if not exists, return[-TINF, -TINF)
        std::pair<T, T> covered_by(const T l, const T r) {
            assert(l <= r);
            if(l == r) return {-TINF, -TINF};
            auto itr = prev(st.upper_bound({l, TINF}));
            if(itr->first <= l and r <= itr->second) return *itr;
            return {-TINF, -TINF};
        }
        // return section which covers[x, x + 1)
        // if not exists, return[-TINF, -TINF)
        std::pair<T, T> covered_by(const T x) { return covered_by(x, x + 1); }
        // insert[l, r), and return increment
        T insert(T l, T r) {
            assert(l <= r);
            if(l == r) return T(0);
            auto itr = prev(st.upper_bound({l, TINF}));
            if(itr->first <= l and r <= itr->second) return T(0);
            T sum_erased = T(0);
            if(itr->first <= l and l <= itr->second) {
                l = itr->first;
                sum_erased += itr->second - itr->first;
                itr = st.erase(itr);
            } else
                itr = next(itr);
            while(r > itr->second) {
                sum_erased += itr->second - itr->first;
                itr = st.erase(itr);
            }
            if(itr->first <= r) {
                sum_erased += itr->second - itr->first;
                r = itr->second;
                st.erase(itr);
            }
            st.emplace(l, r);
            sum += r - l - sum_erased;
            return r - l - sum_erased;
        }
        // insert[x, x + 1), and return increment
        T insert(const T x) { return insert(x, x + 1); }
        // erase [l, r), and return decrement
        T erase(const T l, const T r) {
            assert(l <= r);
            if(l == r) return T(0);
            auto itr = prev(st.upper_bound({l, TINF}));
            if(itr->first <= l and r <= itr->second) {
                if(itr->first < l) st.emplace(itr->first, l);
                if(r < itr->second) st.emplace(r, itr->second);
                st.erase(itr);
                sum -= r - l;
                return r - l;
            }
            T ret = T(0);
            if(itr->first <= l and l < itr->second) {
                ret += itr->second - l;
                if(itr->first < l) st.emplace(itr->first, l);
                itr = st.erase(itr);
            } else
                itr = next(itr);
            while(itr->second <= r) {
                ret += itr->second - itr->first;
                itr = st.erase(itr);
            }
            if(itr->first < r) {
                ret += r - itr->first;
                st.emplace(r, itr->second);
                st.erase(itr);
            }
            sum -= ret;
            return ret;
        }
        // erase [x, x + 1), and return decrement
        T erase(const T x) { return erase(x, x + 1); }
        int size() const { return (int)st.size() - 2; }
        T mex(const T x = 0) const {
            auto itr = prev(st.upper_bound({x, TINF}));
            if(itr->first <= x and x < itr->second)
                return itr->second;
            else
                return x;
        }
        T sum_all() const { return sum; }
        std::set<std::pair<T, T>> get() const {
            std::set<std::pair<T, T>> res;
            for(auto &p : st) {
                if(std::abs(p.first) == TINF) continue;
                res.emplace(p.first, p.second);
            }
            return res;
        }
        void dump() const {
            std::cout << "range_set:";
            for(auto &p : st) {
                if(std::abs(p.first) == TINF) continue;
                std::cout << "[" << p.first << "," << p.second << "),";
            }
            std::cout << '\n';
        }
};

int main(){
    cin.tie(0);
    ios_base::sync_with_stdio(false);
    ll D, Q; cin >> D >> Q;
    range_set<ll> rs;
    ll ans = 0;
    rep(_,Q){
        ll A, B; cin >> A >> B;
        rs.insert(A, B + 1);
        auto [l, r] = rs.covered_by(A, B + 1);
        chmax(ans, r - l);
        cout << ans << endl;
    }
}