### Indian National Olympiad in Informatics

### Online Programming Contest, 5-6 February 2005

### Basic Division

Problem 1: Electoral Rolls Revision, *(K Narayan Kumar, CMI)*

The Chief Electoral Officer of Siruseri has ordered a revision of
the electoral rolls. Siruseri is divided into a number of
*Blocks* and an officer is assigned to each block to enumerate
the list of voters in the block. Siruseri is a model town and assigns
a unique identification number (ID number) to each resident at the
time of his birth and he has to quote this in all his dealings with
the government. The list compiled by the officer is a listing of the
ID numbers of all the voters in his block. This list is in ascending
order of ID numbers.

Once he obtains the lists from all the blocks the CEO will combine
the lists to get a listing of the ID numbers of all eligible voters
in Siruseri. Your task is to help him compile this sorted list from
the sorted lists he gets from the different blocks.

Here is an example with four blocks. The listing of the
voters in the four blocks is as follows:

349 448 900
23 1045 1149 9876
785 1002
456 998 1047 9023 9987

Then, the CEO would like to combine these to get the list:

23 349 448 456 785 900 998 1002 1045 1047 1149 9023 9876 9987

Input format

The first line of the input contains a single integer *B*
indicating the number of blocks in Siruseri. The next *B* lines
(lines 2, ..., * B*+1) contain the voters list from the
different blocks. Line *i*+1 contains the voters list of block
*i*. It consists of a sequence of integers. The first integer
indicates the number of voters in Block *i*. This is followed
by *i* integers, sorted in ascending order, giving the ID
numbers of the voters in this block.

Output format

A sequence of integers, *one in each line*, giving the
sorted sequence of ID numbers, in ascending order, of the voters in
Siruseri.

Test data

You may assume that *B* ≤ 500 and that the number of
voters in every block is not more than 1000. Further, you may assume
that in 50% of the test inputs, *B* ≤ 60 and each block has
at the most 100 voters.

Example

We now illustrate input and output formats using the example described
above.

Sample input:

4
3 349 448 900
4 23 1045 1149 9876
2 785 1002
5 456 998 1047 9023 9987

Sample output:

23
349
448
456
785
900
998
1002
1045
1047
1149
9023
9876
9987