#include <bits/stdc++.h>
using namespace std;
using ll = long long;
constexpr int MOD = 998244353;
#define rep(i, n) for (int i = 0; i < (int)(n); i++)
#define rep2(i, l, r) for (int i = (l); i < (int)(r); i++)

namespace Lib {
struct range_set {
  using all2 = array<long long, 2>;
  static constexpr ll minf = numeric_limits<ll>::min();
  static constexpr ll pinf = numeric_limits<ll>::max();
  set<all2> intervals;
  int add(all2 a) {
    auto [l, r] = a;
    int ret = 1;
    // 既存の区間に完全に包含される場合
    {
      auto it = intervals.upper_bound(all2({l, pinf}));
      if (it != intervals.begin()) {
        it--;
        if ((*it)[1] >= r) return 0;
        if ((*it)[1] >= l) l = (*it)[0];
      }
    }
    auto it = intervals.lower_bound(all2({l, minf}));
    while (1) {
      if (it != intervals.end() && (*it)[0] <= r) {
        r = max(r, (*it)[1]);
        auto it2 = it;
        it++;
        intervals.erase(it2);
        ret -= 1;
      } else {
        break;
      }
    }
    intervals.insert({l, r});
    return ret;
  }
  int erase(all2 a) {
    auto [l, r] = a;
    int ret = 0;
    {
      auto it = intervals.lower_bound(all2({l, minf}));
      if (it != intervals.begin()) {
        it--;
        if ((*it)[1] > l) {
          auto [l2, r2] = *it;
          intervals.erase(it);
          intervals.insert({l2, l});
          if (r2 > r) {
            intervals.insert({r, r2});
            ret += 1;
          }
        }
      }
    }
    auto it = intervals.lower_bound(all2({l, minf}));
    while (1) {
      if (it != intervals.end() && (*it)[1] <= r) {
        auto it2 = it;
        it++;
        intervals.erase(it2);
        ret -= 1;
      } else {
        break;
      }
    }
    if (it != intervals.end() && (*it)[0] < r) {
      auto [l2, r2] = *it;
      intervals.erase(it);
      intervals.insert({r, r2});
    }
    return ret;
  }
  pair<bool, all2> cover(all2 b) {
    auto [l, r] = b;
    auto it = intervals.upper_bound(all2({l, pinf}));
    if (it != intervals.begin()) {
      it--;
      if ((*it)[0] <= l && r <= (*it)[1]) {
        all2 ret = *it;
        return make_pair(true, ret);
      }
    }
    return make_pair(false, all2({0, 0}));
  }
};

}  // namespace Lib

int main() {
  ios::sync_with_stdio(false);
  cin.tie(nullptr);
  Lib::range_set S;
  ll D, Q;
  cin >> D >> Q;
  ll ans = 0;
  while (Q--) {
    ll A, B;
    cin >> A >> B;
    S.add({A, B + 1});
    auto [ok, lr] = S.cover({A, A + 1});
    assert(ok);
    ans = max(ans, lr[1] - lr[0]);
    cout << ans << '\n';
  }
}