#include <bits/stdc++.h>
using namespace std;

#define int long long
#define rep(i, n) for (int i = 0; i < (int) (n); i++)
#define reps(i, n) for (int i = 1; i <= (int) (n); i++)
#define all(x) (x).begin(), (x).end()
#define uniq(x) (x).erase(unique(all(x)), (x).end())
#define bit(n) (1LL << (n))
#define dump(x) cerr << #x " = " << (x) << endl
using vint = vector<int>;
using vvint = vector<vint>;
using pint = pair<int, int>;
using vpint = vector<pint>;
template<typename T> using priority_queue_rev = priority_queue<T, vector<T>, greater<T>>;
constexpr double PI = 3.1415926535897932384626433832795028;
constexpr int DY[9] = {0, 1, 0, -1, 1, 1, -1, -1, 0};
constexpr int DX[9] = {1, 0, -1, 0, 1, -1, -1, 1, 0};
int sign(int x) { return (x > 0) - (x < 0); }
int gcd(int a, int b) {
    while (b) { swap(a %= b, b); }
    return a;
}
int lcm(int a, int b) { return a / gcd(a, b) * b; }
int cdiv(int a, int b) { return (a - 1 + b) / b; }
template<typename T> void fin(T mes) {
    cout << mes << endl;
    exit(0);
}
template<typename T, typename U> bool chmax(T &a, const U &b) {
    if (a < b) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> bool chmin(T &a, const U &b) {
    if (b < a) {
        a = b;
        return true;
    }
    return false;
}
template<typename T, typename U> ostream &operator<<(ostream &os, const pair<T, U> &rhs) {
    os << "(" << rhs.first << ", " << rhs.second << ")";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const vector<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const deque<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T> ostream &operator<<(ostream &os, const set<T> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
template<typename T, typename U> ostream &operator<<(ostream &os, const map<T, U> &rhs) {
    os << "{";
    for (auto itr = rhs.begin(); itr != rhs.end(); itr++) {
        os << *itr << (next(itr) != rhs.end() ? ", " : "");
    }
    os << "}";
    return os;
}
struct setup {
    static constexpr int PREC = 20;
    setup() {
        cout << fixed << setprecision(PREC);
        cerr << fixed << setprecision(PREC);
    };
} setup;

template<typename M>
std::vector<typename M::T> dijkstra(const std::vector<std::vector<int>> &adj,
                                    const std::vector<std::vector<typename M::E>> &cost,
                                    int s) {
    using T = typename M::T;
    int n = adj.size();
    assert(0 <= s && s < n);
    std::vector<T> ret(n, M::ab());
    using P = std::pair<T, int>;
    auto c = [&](P a, P b) -> bool { return M::gr(a.first, b.first); };
    std::priority_queue<P, std::vector<P>, decltype(c)> pq(c);
    ret[s] = M::id();
    pq.push({ret[s], s});
    while (!pq.empty()) {
        P p = pq.top();
        pq.pop();
        int v = p.second;
        if (M::gr(p.first, ret[v])) { continue; }
        for (int i = 0; i < adj[v].size(); i++) {
            int u = adj[v][i];
            T dist = M::op(ret[v], cost[v][i]);
            if (M::gr(ret[u], dist)) { ret[u] = dist, pq.push({ret[u], u}); }
        }
    }
    return ret;
}

struct int_dij {
    using T = int;
    using E = int;
    static T id() { return 0; }
    static T ab() { return std::numeric_limits<T>::max(); }
    static T op(const T &a, const E &b) { return a == ab() ? ab() : a + b; }
    static bool gr(const T &a, const T &b) { return a > b; }
};

vint solve0(int H, int W, vint A, vint B) {
    A.resize(H + 1), B.resize(H + 1);
    set<pint> st;
    reps(i, W) { st.insert({i, 0}); }
    vvint adj(2 * (H + 1)), cost(2 * (H + 1));
    A[H] = 1, B[H] = W;
    rep(i, H + 1) {
        auto p0 = st.lower_bound({A[i], 0}), p1 = st.upper_bound({B[i], i});
        for (auto pc = p0; pc != p1; pc++) {
            adj[pc->second + H + 1].emplace_back(i);
            cost[pc->second + H + 1].emplace_back(i - pc->second);
            adj[pc->second + H + 1].emplace_back(i + H + 1);
            cost[pc->second + H + 1].emplace_back(i - pc->second + B[i] + 1 - pc->first);
        }
        st.erase(p0, p1);
        st.insert({B[i] + 1, i});
    }
    //dump(adj), dump(cost);
    vint d = dijkstra<int_dij>(adj, cost, H + 1);
    for (int i = H - 1; i > 0; i--) { chmin(d[i], d[i + 1] - 1); }
    vint ans;
    reps(i, H) {
        if (d[i] > INT_MAX) { ans.push_back(-1); }
        else { ans.emplace_back(d[i]); }
    }
    return ans;
}

vint solve1(int H, int W, vint A, vint B) {
    vector dp(H + 1, vint(W + 1));
    rep(i, H + 1) { dp[i][0] = INT_MAX; }
    vint ans;
    reps(i, H) {
        int cur = INT_MAX;
        reps(j, W) {
            dp[i][j] = dp[i][j - 1] + 1;
            if (A[i - 1] > j || j > B[i - 1]) { chmin(dp[i][j], dp[i - 1][j] + 1); }
            chmin(cur, dp[i][j]);
        }
        if (cur >= INT_MAX) { cur = -1; }
        ans.emplace_back(cur);
    }
    return ans;
}

long long xor64(long long range) {
    static unsigned long long x = 114514191810ULL;
    x ^= x << 13;
    x ^= x >> 7;
    return (x ^= x << 17) % range;
}

signed main() {
    /*
    rep(_, 1000) {
        int H = xor64(10) + 1, W = xor64(10) + 1;
        vint A(H), B(H);
        rep(i, H) {
            A[i] = xor64(W) + 1, B[i] = xor64(W) + 1;
            if (A[i] > B[i]) { swap(A[i], B[i]); }
        }
        vint res0 = solve0(H, W, A, B), res1 = solve1(H, W, A, B);
        if (res0 != res1) {
            dump(H), dump(W), dump(A), dump(B), dump(res0), dump(res1);
            break;
        }
    }
    */
    int H, W;
    cin >> H >> W;
    vint A(H), B(H);
    rep(i, H) { cin >> A[i] >> B[i]; }
    vint ans = solve0(H, W, A, B);
    for (int a:ans) { cout << a << endl; }
}


Measured memory_bytes: 62412