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Simple Merge

Estimated time limit: 0.5 seconds. Memory limit: 128 MB.

On the target judge, multiply the reference program's largest per-case median time by \(2\) and round up to a multiple of \(0.5\) seconds. See environment and measurements.

Story

Items in a warehouse form several monotone sequences of labels. Report the labels as the smallest remaining item is repeatedly removed.

(This story was rewritten by GPT-6.)

Formal Problem Statement

You are given \(k\) nonempty integer sequences. Each is either nondecreasing or nonincreasing; their directions may differ. Equal elements are allowed within and across sequences.

Perform \(m\) operations. In each operation, print the smallest value among all remaining elements, then remove one occurrence of that value. The order of removing equal occurrences does not affect the output.

Input Format

The first line contains \(k,m\) . Each of the next \(k\) lines describes one sequence: its length \(s_i\) , followed by its \(s_i\) elements \(x_{i,1},\ldots,x_{i,s_i}\) .

Output Format

Print \(m\) lines containing the removed values in order. If \(m=0\) , produce no output.

Examples

Example 1

Input

3 10
3 1 2 3
5 1 2 3 4 8
6 1 5 7 9 10 11

Output

1
1
1
2
2
3
3
4
5
7

Example 2

Input

3 6
2 5 -1
2 -1 -1
2 0 4

Output

-1
-1
-1
0
4
5

Example 3

Input

1 1
1 -1000000000

Output

-1000000000

Example Explanation

In the first example, each sequence contains one \(1\) , so the first three outputs are all \(1\) . The second example includes a decreasing sequence and repeated negative values; every occurrence is retained.

Constraints and Guarantees

All inputs satisfy: \(1\le k\le31\) , \(s_i\ge1\) , \(0\le m\le\sum s_i\le10^6\) , and \(\lvert x_{i,j}\rvert\le10^9\) . Every sequence satisfies the stated monotonicity guarantee.

Score Additional conditions
100% None