#include <bits/stdc++.h>

#define rep(i,n) for(int i=0;i<(int)(n);i++)
#define FOR(i,n,m) for(int i=(int)(n); i<=(int)(m); i++)
#define RFOR(i,n,m) for(int i=(int)(n); i>=(int)(m); i--)
#define ITR(x,c) for(__typeof(c.begin()) x=c.begin();x!=c.end();x++)
#define RITR(x,c) for(__typeof(c.rbegin()) x=c.rbegin();x!=c.rend();x++)
#define setp(n) fixed << setprecision(n)

template<class T> bool chmax(T &a, const T &b) { if (a<b) { a=b; return 1; } return 0; }
template<class T> bool chmin(T &a, const T &b) { if (a>b) { a=b; return 1; } return 0; }

#define ll long long
#define vll vector<ll>
#define vi vector<int>
#define pll pair<ll,ll>
#define pi pair<int,int>

#define all(a) (a.begin()),(a.end())
#define rall(a) (a.rbegin()),(a.rend())
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define ins insert

using namespace std;

const int INF = 1e9;

//-------------------------------------------------
//--Lazy Evaluation Segment tree (Proportional)
//-------------------------------------------------
template<typename T, typename E>
class LazySegmentTree
{
private:
    const T te=INF;
    const E ee=INF;
    inline T f(T x, T y){return min(x,y);}
    inline T g(T x, E y){return y;}
    inline E h(E x, E y){return (y==ee)?x:y;}
    int n, height;
    ::std::vector<T> seg;
    ::std::vector<E> lazy;
public:
    LazySegmentTree(int _n){
        init(_n);
    }
    void init(int _n){
        n = 1; height=0;
        while(n<_n) n<<=1, height++;
        seg.resize(2*n, te);
        lazy.resize(2*n, ee);
    }
    void build(){
        for(int i=n-1; i>0; i--) seg[i] = f(seg[i<<1], seg[i<<1|1]);
    }
    T eval(int k){
        int c = breadth(k);
        return (lazy[k]==ee) ? seg[k] : g(seg[k],quantify(lazy[k], c));
    }
    void waveto(int k){
        for(int i=height; i>0; i--) wave(k>>i);
    }
    void wave(int k){
        seg[k] = eval(k);
        lazy[k<<1] = h(lazy[k<<1],lazy[k]);
        lazy[k<<1|1] = h(lazy[k<<1|1],lazy[k]);
        lazy[k] = ee;
    }
    void recalc(int k){
        for(int i=1; i<=height; i++){
            int m = k>>i;
            seg[m] = f(eval(m<<1), eval(m<<1|1));
        }
    }
    void update(int a, int b, E x){
        if (b<=a) return;
        waveto(a+=n);
        waveto(b+=n-1);
        T L=ee, R=ee;
        int l=a, r=b;
        while(l<=r){
            if (l&1) lazy[l] = h(lazy[l], x), l++;
            if (!(r&1)) lazy[r] = h(lazy[r], x), r--;
            l>>=1; r>>=1;
        }
        recalc(a);
        recalc(b);
    }
    T query(int a, int b){
        waveto(a+=n);
        waveto(b+=n-1);
        T L=te, R=te;
        int l=a, r=b;
        while(l<=r){
            if (l&1) L = f(L, eval(l++));
            if (!(r&1)) R = f(eval(r--), R);
            l>>=1; r>>=1;
        }
        return f(L,R);
    }
    T operator[](int k){return query(k, k+1);};
    inline int breadth(int k){
        int ret = height-31+__builtin_clz(k);
        return 1<<ret;
    }
    //return value proportional to segment's width
    inline E quantify(E laz, int c){
        return laz;
    }
};

struct Event{
    int id,x,y;
    bool operator<(const Event &e) const {
        return (x!=e.x)?(x<e.x):(id!=e.id)?(id<e.id):(y>e.y);
    }
};

//-------------------------------------------------

int main(void)
{
    cin.tie(0);
    ios::sync_with_stdio(false);
    int H,W; cin>>H>>W;
    vector<Event> events;
    vi right(H);
    rep(i,H){
        int a,b; cin>>a>>b; a--; b--;
        events.pb({0,a,i});
        events.pb({1,b+1,i});
        right[i] = b+1;
    }
    rep(i,W) events.pb({2,i,0});
    events.pb({0,0,H});
    events.pb({1,W,H});

    sort(all(events));
    set<int> Set;
    vi start(W), next(H+1,-1);
    for(auto e:events){
        // insert
        if (e.id==0){
            Set.ins(e.y);
        }
        // erase
        if (e.id==1){
            Set.erase(e.y);
            auto itr = Set.upper_bound(e.y);
            if (itr!=Set.end()){
                next[e.y] = *itr;
            }
        }
        // check
        if (e.id==2){
            start[e.x] = *Set.begin();
        }
    }

    using P = tuple<int,int,int>;
    vector<P> update;
    update.pb({0,0,*max_element(all(start))+1});

    vector<bool> seen(H+1);
    RFOR(i,W-1,0){
        int cur = start[i];
        while(next[cur]!=-1 && !seen[cur]){
            update.pb({right[cur]-i,cur+1,next[cur]+1});
            seen[cur] = true;
            cur = next[cur];
        }
    }

    LazySegmentTree<int,int> seg(H+1);
    sort(rall(update));
    for(auto [val,a,b]:update){
        seg.update(a,b,val);
    }
    rep(i,H){
        int ans = seg[i+1];
        cout<<(ans==INF?-1:ans+i+1)<<"\n";
    }
    return 0;
}


Measured memory_bytes: 20012