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# Solution in PHP

All solutions, regardless of the programming language, are tested by an automatic system. The test system creates an isolated, empty environment for your program and runs it several times with a different set of input data. After that, the test system compares the output of the program with the expected result using a special algorithm.

The test system does not analyze the program code, does not check its contents, formatting, variable names, program size, etc.

In case program uses files for input and output, standard input-output streams (stdin and stdout) are ignored. In case program uses standard input-output streams (stdin and stdout), the test system does not analyze any files created by the solution.

The input data always corresponds to the constraints specified in the problem statement. Your solution does not need to verify the correctness of the input, unless this explicitly mentioned in the problem statement. Be careful, the lines in the input data are separated by the newline character \nor by combination of the carriage return and new line symbols:\r\n. The program should correctly handle both formats.

All output data is considered to be answer for the test, so if your program displays additional messages, for example, "Enter a number" or "Answer:" the solution will not be accepted. Follow the instructions in the problem statement to format answer correctly.

You can submit solutions written in the PHP programming language using the PHP compiler. The test system uses php 5.6 compiler, which runs on the Alpine Linux 3.6.

In case program produces an error, the test system marks test run as "Runtime Error".

An example of a solution for simple problem in PHP:

<?php
$input = trim(stream_get_contents(STDIN)); echo$input[0] . " " . \$input[1] . "\n";