https://brain-beats.in/lab/filter-alt.js

1// Import the fs module
2const fs = require('node:fs');
3
4// Define the input and output file paths
5const inputFile = 'spooky-formatted-frequency-3.txt';
6const outputFile = 'spooky-alt-frequency.txt';
7
8// Define the condition to filter the lines
9const condition = 'ALT \r';
10
11// Read the input file asynchronously
12fs.readFile(inputFile, 'utf8', (err, data) => {
13  // Handle any errors
14  if (err) {
15    console.error(err);
16    return;
17  }
18  // Split the data into an array of lines
19  const lines = data.split('\n');
20  // console.log(lines);
21  // Filter the lines that end with the condition
22  const filteredLines = lines.filter(line => line.endsWith(condition));
23  console.log(filteredLines);
24  // Join the filtered lines into a string
25  const outputData = filteredLines.join('\n');
26  // Write the output data to the output file asynchronously
27  fs.writeFile(outputFile, outputData, err => {
28    // Handle any errors
29    if (err) {
30      console.error(err);
31      return;
32    }
33    // Log a success message
34    console.log('Output file written successfully');
35  });
36});