JavaScript Interview Prep: Sparse Arrays

Prompt

There is a collection of input strings and a collection of query strings. For each query string, determine how many times it occurs in the list of input strings. Return an array of the results.

Solution

'use strict';

const fs = require('fs');

process.stdin.resume();
process.stdin.setEncoding('utf-8');

let inputString = '';
let currentLine = 0;

process.stdin.on('data', function(inputStdin) {
    inputString += inputStdin;
});

process.stdin.on('end', function() {
    inputString = inputString.split('\n');

    main();
});

function readLine() {
    return inputString[currentLine++];
}

/*
 * Complete the 'matchingStrings' function below.
 *
 * The function is expected to return an INTEGER_ARRAY.
 * The function accepts following parameters:
 *  1. STRING_ARRAY strings
 *  2. STRING_ARRAY queries
 */

function matchingStrings(strings, queries) {
    // Write your code here'

    const resArr = new Array(queries.length);
    console.log(resArr);
    queries.forEach((each, eachIndex) => {
        let count = 0;
        strings.forEach((each1, each1Index) => {
            if (each == each1){
                count++;
            }
        });
        resArr[eachIndex] = count;
    });
    
    console.log(resArr);
    return resArr;

}

function main() {
    const ws =…