Word Frequency

LeetCode 192 | Difficulty: Medium

Medium

Problem Description

Write a bash script to calculate the frequency of each word in a text file words.txt.

For simplicity sake, you may assume:

• words.txt contains only lowercase characters and space ' ' characters.

• Each word must consist of lowercase characters only.

• Words are separated by one or more whitespace characters.

Example:

Assume that words.txt has the following content:

the day is sunny the the
the sunny is is

Your script should output the following, sorted by descending frequency:

the 4
is 3
sunny 2
day 1

Note:

• Don't worry about handling ties, it is guaranteed that each word's frequency count is unique.

• Could you write it in one-line using Unix pipes?

Topics: Shell

---

Solutions

Solution 1: bash (Best: 132 ms)

Metric	Value
Runtime	132 ms
Memory	3.8 MB
Date	2022-02-17

Solution

# Read from the file words.txt and output the word frequency list to stdout.
cat words.txt | tr -s ' ' '\n' | sort | uniq --count | sort -r | awk '{print $2 " " $1}'

---

Complexity Analysis

Approach	Time	Space
Solution	$O(n)$	$O(1) to O(n)$

---

Interview Tips

Key Points

• Discuss the brute force approach first, then optimize. Explain your thought process.