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JavaScript: Find the shortest possible string which can create a string to make it a palindrome by adding characters to the end of it

JavaScript Basic: Exercise-97 with Solution

Write a JavaScript program to find the shortest possible string which can create a string to make it a palindrome by adding characters to the end of it.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title> Find the shortest possible string which can create a string to make it a palindrome by adding characters to the end of it</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function build_Palindrome(new_str) {
  var flag;
  for (var i = new_str.length;; i++) {
    flag = true;
    for (var j = 0; j < i - j - 1; j++) {
      if (i - j - 1 < new_str.length && new_str[j] != new_str[i - j - 1]) {
        flag = false;
        break;
      }
    }
    if (flag) {
      for (var j = new_str.length; j < i; j++) {
        new_str += new_str[i - j - 1];
      }
      return new_str;
    }
  }
}

console.log(build_Palindrome("abcddc"))
console.log(build_Palindrome("122"))

Sample Output:

abcddcba
1221

Flowchart:

Flowchart: JavaScript - Find the shortest possible string which can create a string to make it a palindrome by adding characters to the end of it

ES6 Version:

function build_Palindrome(new_str) {
  let flag;
  for (let i = new_str.length;; i++) {
    flag = true;
    for (var j = 0; j < i - j - 1; j++) {
      if (i - j - 1 < new_str.length && new_str[j] != new_str[i - j - 1]) {
        flag = false;
        break;
      }
    }
    if (flag) {
      for (var j = new_str.length; j < i; j++) {
        new_str += new_str[i - j - 1];
      }
      return new_str;
    }
  }
}

console.log(build_Palindrome("abcddc"))
console.log(build_Palindrome("122"))

Live Demo:

See the Pen javascript-basic-exercise-97 by w3resource (@w3resource) on CodePen.


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Next: Write a JavaScript program to switch case of the minimum possible number of letters to make a given string written in the upper case or in the lower case.

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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