Javascript – Logging unnecessary lines on running the code

I need help with my nodejs code

const fs = require('fs');

function processFile(filePath) {
  const content = fs.readFileSync(filePath, 'utf-8');
  const lines = content.split('n');

  const wordIdMaps = lines.map(() => ({ wordIdMap: {}, currentId: 1 }));

  lines.forEach((line, index) => {
    const words = line.split(' ');
    const wordIdMap = wordIdMaps[index].wordIdMap;
    let currentId = wordIdMaps[index].currentId;

    words.forEach((word) => {
      if (!wordIdMap[word]) {
        wordIdMap[word] = currentId;
        currentId++;
      }
    });
  });

  return { lines, wordIdMaps }; // Return both lines and wordIdMaps
}

function customConsoleLog(logFormat, wordIdMaps) {
  const lines = wordIdMaps.map((map) => Object.entries(map.wordIdMap).map(([word, id]) => `${word}:${id}`).join(' '));

  lines.forEach((line, index) => {
    const wordIdMap = wordIdMaps[index].wordIdMap;

    const replacedLog = logFormat.replace(/${(d+)}/g, (_, id) => {
      const word = Object.keys(wordIdMap).find((key) => wordIdMap[key] == id);
      return word !== undefined ? word : '${' + id + '}';
    });

    const words = line.split(' ');
    const replacedLine = replacedLog.replace(/${d+}/g, (match) => {
      const id = match.slice(2, -1);
      return words[id - 1] !== undefined ? words[id - 1] : match;
    });

    console.log(replacedLine);
  });
}

// Command-line arguments
const filePath = process.argv[2];
const logFormat = process.argv[3];

if (!filePath || !logFormat) {
  console.log('Please provide both a file path and a custom console log format as command-line arguments.');
} else {
  const { lines, wordIdMaps } = processFile(filePath);

  customConsoleLog(logFormat, wordIdMaps);
}

This nodejs code takes data from a txt file and provides custom output through command line argument
If I write:

node index.js test.txt '${1} ${2} ${3} ${4}'

The code splits the file content’s lines and then splits the words by whitespace, and provides the output in which it reads and lists first four words of every line of the file content, for example:

apple boy cat dog
elephant fish god hen

But the output creates an extra line of IDs after listing out all the lines

apple boy cat dog
elephant fish god hen
 ${2} ${3} ${4}

How can I fix this error?