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JavaScript: Compute the sum of all digits that occur in a given string

JavaScript Basic: Exercise-147 with Solution

Write a JavaScript program to compute the sum of all digits that occur in a given string.

Pictorial Presentation:

JavaScript: Compute the sum of all digits that occur in a given string.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title>Compute the sum of all digits that occur in a given string.</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function sum_digits_from_string(dstr) {
  var dsum = 0;

  for (var i = 0; i < dstr.length; i++)
  {

    if (/[0-9]/.test(dstr[i])) dsum += parseInt(dstr[i])
  }
  return dsum;
}

console.log(sum_digits_from_string("abcd12efg9"))
console.log(sum_digits_from_string("w3resource"))

Sample Output:

12
3

Flowchart:

Flowchart: JavaScript - Compute the sum of all digits that occur in a given string

ES6 Version:

function sum_digits_from_string(dstr) {
  let dsum = 0;

  for (let i = 0; i < dstr.length; i++)
  {

    if (/[0-9]/.test(dstr[i])) dsum += parseInt(dstr[i])
  }
  return dsum;
}

console.log(sum_digits_from_string("abcd12efg9"))
console.log(sum_digits_from_string("w3resource"))

Live Demo:

See the Pen javascript-basic-exercise-147 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript program to compute the sum of cubes of all integer from 1 to a given integer.
Next: Write a JavaScript program to swap two halves of a given array of integers of even length.

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JavaScript: Tips of the Day

Parameter's value

function getItems(fruitList, ...args, favoriteFruit) {
  return [...fruitList, ...args, favoriteFruit]
}

getItems(["banana", "apple"], "pear", "orange")

...args is a rest parameter. The rest parameter's value is an array containing all remaining arguments, and can only be the last parameter! In this example, the rest parameter was the second parameter. This is not possible, and will throw a syntax error.

function getItems(fruitList, favoriteFruit, ...args) {
  return [...fruitList, ...args, favoriteFruit];
}


getItems(['banana', 'apple'], 'pear', 'orange');
The above example works. This returns the array [ 'banana', 'apple', 'orange', 'pear' ].

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