 
 Data Structure Data Structure
 Networking Networking
 RDBMS RDBMS
 Operating System Operating System
 Java Java
 MS Excel MS Excel
 iOS iOS
 HTML HTML
 CSS CSS
 Android Android
 Python Python
 C Programming C Programming
 C++ C++
 C# C#
 MongoDB MongoDB
 MySQL MySQL
 Javascript Javascript
 PHP PHP
- Selected Reading
- UPSC IAS Exams Notes
- Developer's Best Practices
- Questions and Answers
- Effective Resume Writing
- HR Interview Questions
- Computer Glossary
- Who is Who
Modify an array based on another array JavaScript
Suppose, we have a reference array of phrases like this −
const reference = ["your", "majesty", "they", "are", "ready"];
And we are required to join some of the elements of above array based on another array so if another array is this −
const another = ["your", "they are"];
The result would be like −
result = ["your", "majesty", "they are", "ready"];
Here, we compared the elements in both the arrays, we joined the elements of the first array if they existed together in the second array.
We are required to write a JavaScript function that takes in two such arrays and returns a new joined array.
Example
const reference = ["your", "majesty", "they", "are", "ready"];
const another = ["your", "they are"];
const joinByReference = (reference = [], another = []) => {
   const res = [];
   const filtered = another.filter(a => a.split(" ").length > 1);
   while(filtered.length) {
      let anoWords = filtered.shift();
      let len = anoWords.split(" ").length;
      while(reference.length>len) {
         let refWords = reference.slice(0,len).join(" ");
         if (refWords == anoWords) {
            res.push(refWords);
            reference = reference.slice(len,reference.length);
            break;
         };
         res.push(reference.shift());
      };
   };
   return [...res, ...reference];
};
console.log(joinByReference(reference, another));
Output
This will produce the following output −
[ 'your', 'majesty', 'they are', 'ready' ]
Advertisements
                    