Remove duplicate words from a sentence.

Difficulty: Hard

Phase: 6 · Mixed Logical Challenges

XP Reward: 30 XP

Topics: Mixed Logical Challenges, Hard

Supported Languages: Python, JavaScript, C, C++, Java

Problem Description

Given R and C followed by an R x C matrix, print its boundary elements in clockwise order starting from (0,0) separated by space. Input Format: Read input from standard input (stdin). Output Format: Print the result to standard output (stdout).

Constraints

-10^9 <= N <= 10^9

Examples

Example 1

Input: 3 3 1 2 3 4 5 6 7 8 9

Output: 1 2 3 6 9 8 7 4

Explanation: Sample execution for input 3 3 1 2 3 4 5 6 7 8 9