How to decrease size of a string by using preceding numbers - JavaScript?

Let’s say our original string is the following with repeated letters −

var values = "DDAAVIDMMMILLERRRRR";

We want to remove the repeated letters and precede letters with numbers. For this, use replace() along with regular expression.

Example

Following is the code −

var values = "DDAAVIDMMMILLERRRRR";
var precedingNumbersInString = values.replace(/(.)\1+/g, obj => obj.length + obj[0]);
console.log("The original string value=" + values);
console.log("String value after preceding the numbers =");
console.log(precedingNumbersInString);

To run the above program, you need to use the following command −

node fileName.js.

Here, my file name is demo295.js.

Output

This will produce the following output on console −

PS C:\Users\Amit\javascript-code> node demo295.js
The original string value=DDAAVIDMMMILLERRRRR
String value after preceding the numbers =
2D2AVID3MI2LE5R