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JavaScript: Swap pairs of adjacent digits of a given integer of even length

JavaScript Basic: Exercise-150 with Solution

Write a JavaScript program to swap pairs of adjacent digits of a given integer of even length.

Pictorial Presentation:

JavaScript: Swap pairs of adjacent digits of a given integer of even length.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Swap pairs of adjacent digits of a given integer of even length.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function swap_adjacent_digits(n)
{
   if (n.toString().length%2!=0)
     {
       return false;
     }
  var result = 0,
		x = 1;
	while (n != 0) {
		var dg1 = n % 10,
			dg2 = ((n - dg1) / 10) % 10;
		result += x * (10 * dg1 + dg2);
		n = Math.floor(n / 100);
		x *= 100;
	}
	return result;
}
console.log(swap_adjacent_digits(15));
console.log(swap_adjacent_digits(1234));
console.log(swap_adjacent_digits(123456));
console.log(swap_adjacent_digits(12345));

Sample Output:

51
2143
214365
false

Flowchart:

Flowchart: JavaScript - swap pairs of adjacent digits of a given integer of even length

ES6 Version:

function swap_adjacent_digits(n) {
  if (n.toString().length % 2 != 0) {
    return false;
  }

  var result = 0,
      x = 1;

  while (n != 0) {
    var dg1 = n % 10,
        dg2 = (n - dg1) / 10 % 10;
    result += x * (10 * dg1 + dg2);
    n = Math.floor(n / 100);
    x *= 100;
  }

  return result;
}

console.log(swap_adjacent_digits(15));
console.log(swap_adjacent_digits(1234));
console.log(swap_adjacent_digits(123456));
console.log(swap_adjacent_digits(12345));

Live Demo:

See the Pen javascript-basic-exercise-150 by w3resource (@w3resource) on CodePen.


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Next: Javascript Functions Exercises.

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JavaScript: Tips of the Day

Classes/function constructors

class Person {
  constructor() {
    this.name = 'Owen';
  }
}

Person = class AnotherPerson {
  constructor() {
    this.name = 'Eddie';
  }
};

const member = new Person();
console.log(member.name);

We can set classes equal to other classes/function constructors. In this case, we set Person equal to AnotherPerson. The name on this constructor is Eddie, so the name property on the new Person instance member is "Eddie".

Ref: https://bit.ly/3jFRBje