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JavaScript: Create a new string from a given string taking the last 3 characters and added at both the front and back

JavaScript Basic: Exercise-26 with Solution

Write a JavaScript program to create a new string from a given string taking the last 3 characters and added at both the front and back. The string length must be 3 or more.

Pictorial Presentation:

JavaScript: Create a new string from a given string taking the last 3 characters and added at both the front and back

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>JavaScript program to create a new string from a given string taking the last 3 characters and added at both the front and back. The string length must be 3 or more.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function front_back3(str)
 {
  if (str.length>=3)
   {
   str_len = 3;
 
  back = str.substring(str.length-3);
   return back + str + back;
 }
   else
     return false;
 }
console.log(front_back3("abc"));
console.log(front_back3("ab"));
console.log(front_back3("abcd"));

Sample Output:

abcabcabc
false
bcdabcdbcd

Flowchart:

Flowchart: JavaScript - Create a new string from a given string taking the last 3 characters and added at both the front and back

ES6 Version:

function front_back3(str)
 {
  if (str.length>=3)
   {
   str_len = 3;
 
  back = str.substring(str.length-3);
   return back + str + back;
 }
   else
     return false;
 }
console.log(front_back3("abc"));
console.log(front_back3("ab"));
console.log(front_back3("abcd"));

Live Demo:

See the Pen JavaScript: added characters added at both the front and back-basic- ex-25 by w3resource (@w3resource) on CodePen.


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JavaScript: Tips of the Day

Checks if a string is an anagram of another string (case-insensitive, ignores spaces, punctuation and special characters)

Example:

const isAnagram = (str1, str2) => {
  const normalize = str =>
    str
      .toLowerCase()
      .replace(/[^a-z0-9]/gi, '')
      .split('')
      .sort()
      .join('');
  return normalize(str1) === normalize(str2);
};
console.log(isAnagram('iceman', 'cinema')); // true

Output:

true