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JavaScript: Find the smallest prime number strictly greater than a given number

JavaScript Basic: Exercise-129 with Solution

Write a JavaScript program to find the smallest prime number strictly greater than a given number.

Pictorial Presentation:

JavaScript: Find the smallest prime number strictly greater than a given number.

Sample Solution:

HTML Code:

<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width">
  <title> Find the smallest prime number strictly greater than a given number</title>
</head>
<body>

</body>
</html>

JavaScript Code:

function next_Prime_num(num) {
    for (var i = num + 1;; i++) {
        var isPrime = true;
        for (var d = 2; d * d <= i; d++) {
            if (i % d === 0) {
                isPrime = false;
                break;
            }
        }
        if (isPrime) {
            return i;
        }
    }
}

console.log(next_Prime_num(3));
console.log(next_Prime_num(17));

Sample Output:

5
19

Flowchart:

Flowchart: JavaScript - Find the smallest prime number strictly greater than a given number

ES6 Version:

function next_Prime_num(num) {
    for (let i = num + 1;; i++) {
        let isPrime = true;
        for (let d = 2; d * d <= i; d++) {
            if (i % d === 0) {
                isPrime = false;
                break;
            }
        }
        if (isPrime) {
            return i;
        }
    }
}

console.log(next_Prime_num(3));
console.log(next_Prime_num(17));

Live Demo:

See the Pen javascript-basic-exercise-129 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript program to find the smallest round number that is not less than a given value.
Next: Write a JavaScript program to find the number of even digits in a given integer.

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JavaScript: Tips of the Day

Converts a string to title case

Example:

const toTitleCase = str =>
  str
    .match(/[A-Z]{2,}(?=[A-Z][a-z]+[0-9]*|\b)|[A-Z]?[a-z]+[0-9]*|[A-Z]|[0-9]+/g)
    .map(x => x.charAt(0).toUpperCase() + x.slice(1))
    .join(' ');
console.log(toTitleCase('some_database_field_name')); // 'Some Database Field Name'
console.log(toTitleCase('Some label that needs to be title-cased')); // 'Some Label That Needs To Be Title Cased'
console.log(toTitleCase('some-package-name')); // 'Some Package Name'
console.log(toTitleCase('some-mixed_string with spaces_underscores-and-hyphens')); // 'Some Mixed String With Spaces Underscores And Hyphens' 

Output:

"Some Database Field Name"
"Some Label That Needs To Be Title Cased"
"Some Package Name"
"Some Mixed String With Spaces Underscores And Hyphens"