Problem: There is a grid of squares with H+1 horizontal rows and W vertical columns.

You will start at one of the squares in the top row and repeat moving one square right or down. However, for each integer i from 1 through H, you cannot move down from the A_i-th, (A_i + 1)-th, \ldots, B_i-th squares from the left in the i-th row from the top.

For each integer k from 1 through H, find the minimum number of moves needed to reach one of the squares in the (k+1)-th row from the top. (The starting square can be chosen individually for each case.) If, starting from any square in the top row, none of the squares in the (k+1)-th row can be reached, print `-1` instead.

Constraints

* 1 \leq H,W \leq 2\times 10^5
* 1 \leq A_i \leq B_i \leq W

Input

Input is given from Standard Input in the following format:


H W
A_1 B_1
A_2 B_2
:
A_H B_H


Output

Print H lines. The i-th line should contain the answer for the case k=i.

Example

Input

4 4
2 4
1 1
2 3
2 4


Output

1
3
6
-1

Solution (in CPP):

Solution:
#define rep(i, n) for (int i = 0; i < (n); i ++)
#include <iostream>
#include <vector>
#include <map>
#include <set>
using namespace std;

int main() {
    int h, w;
    cin >> h >> w;
    map<int,int> s;
    multiset<int> p;
    rep(i, w) s[i] = i;
    rep(i, w) p.insert(0);
    
    rep(i, h){
        int a, b;
        cin >> a >> b;
        --a;
        auto it = s.lower_bound(a);
        int r = -1;
        while(it != s.end() && it->first <= b){
            r = max(r, it->second);
            p.erase(p.find(it->first - it->second));
            s.erase(it ++);
        }
        if(r != -1 && b < w){
            p.insert(b - r);
            s[b] = r;
        }
        int ans = -1;
        if(p.size() > 0){
            ans = *p.begin() + (i + 1);
        }
        printf("%d\n", ans);
        
    }
    
    return 0;
}