Abstract

The Uniq Command 2 problem from HackerRank.

Uniq Command 2

Problem

Uniq Command 2

In this challenge, we practice using the uniq command to eliminate consecutive repetitions of a line when a text file is piped through it.

Given a text file, count the number of times each line repeats itself. Only consider consecutive repetitions. Display the space-separated count and line, respectively. There shouldn’t be any leading or trailing spaces. Please note that the uniq -c command by itself will generate the output in a different format than the one expected here.

Sample Input

00
00
01
01
00
00
02
02
03
aa
aa
aa

Sample Output

2 00
2 01
2 00
2 02
1 03
3 aa

Explanation

00 is repeated twice
01 is repeated twice
00 is repeated twice
02 is repeated twice
03 occurs once
aa is repeated thrice

Solution

uniq-2.sh

#!/usr/bin/env bash

# shellcheck disable=SC2162
uniq -c < /dev/stdin | awk '{$1=$1};1'