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JavaScript: Create a new string from a given string changing the position of first and last characters

JavaScript Basic: Exercise-23 with Solution

Write a JavaScript program to create a new string from a given string changing the position of first and last characters. The string length must be greater than or equal to 1.

Pictorial Presentation:

JavaScript: Create a new string from a given string changing the position of first and last characters

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 changing the position of first and last characters.</title>
</head>
<body>
</body>
</html>

JavaScript Code:

function first_last(str1) 
  {
  if (str1.length <= 1)
  {
    return str1;
  }
  mid_char = str1.substring(1, str1.length - 1);
  return (str1.charAt(str1.length - 1)) + mid_char + str1.charAt(0);
}
console.log(first_last('a'));
console.log(first_last('ab'));
console.log(first_last('abc'));

Sample Output:

a
ba
cba

Flowchart:

Flowchart: JavaScript - Create a new string from a given string changing the position of first and last characters

ES6 Version:

function first_last(str1) 
  {
  if (str1.length <= 1)
  {
    return str1;
  }
  mid_char = str1.substring(1, str1.length - 1);
  return (str1.charAt(str1.length - 1)) + mid_char + str1.charAt(0);
}
console.log(first_last('a'));
console.log(first_last('ab'));
console.log(first_last('abc'));

Live Demo:

See the Pen JavaScript: position of first and last characters.: basic-ex-23 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript program to remove a character at the specified position of a given string and return the new string.
Next: Write a JavaScript program to create a new string from a given string with the first character of the given string added at the front and back.

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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