JavaScript: Insert dashes (-) between each two even digits of a specific number

Last update on May 30 2022 10:05:45 (UTC/GMT +8 hours)

JavaScript Array: Exercise-6 with Solution

Write a JavaScript program which accept a number as input and insert dashes (-) between each two even numbers. For example if you accept 025468 the output should be 0-254-6-8.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
<meta charset=utf-8 />
<title>Insert dashes (-) between even numbers</title>
</head>
<body>
</body>
</html>

JavaScript Code:

const num=window.prompt();
const str = num.toString();
const result = [str[0]];
  
for(let x=1; x<str.length; x++)
  {
    if((str[x-1]%2 === 0)&&(str[x]%2 === 0))
     {
      result.push('-', str[x]);
     }
    else
     {
      result.push(str[x]);
     }
  }
console.log(result.join(''));

Sample Output:

0-254-6-8

Flowchart:

ES6 Version:

var num = window.prompt();
var str = num.toString();
var result = [str[0]];

for (var x = 1; x < str.length; x++) {
  if (str[x - 1] % 2 === 0 && str[x] % 2 === 0) {
    result.push('-', str[x]);
  } else {
    result.push(str[x]);
  }
}
console.log(result.join(''));

Live Demo:

See the Pen JavaScript - Insert dashes (-) between each two even digits of a specific number- array-ex-6 by w3resource (@w3resource) on CodePen.

Improve this sample solution and post your code through Disqus

Previous: Write a simple JavaScript program to join all elements of the following array into a string.
Next: Write a JavaScript program to sort the items of an array.

JavaScript: Tips of the Day

How to insert an item into an array at a specific index (JavaScript)?

What you want is the splice function on the native array object.

arr.splice(index, 0, item); will insert item into arr at the specified index (deleting 0 items first, that is, it's just an insert). In this example we will create an array and add an element to it into index 2:

var arr = []; arr[0] = "Jani"; arr[1] = "Hege"; arr[2] = "Stale"; arr[3] = "Kai Jim"; arr[4] = "Borge"; console.log(arr.join()); arr.splice(2, 0, "Lene"); console.log(arr.join());

Ref: https://bit.ly/2BXbp04