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JavaScript : Hash an given input string into a whole number

JavaScript fundamental (ES6 Syntax): Exercise-99 with Solution

Write a JavaScript program to hash an given input string into a whole number.

Hashes the input string into a whole number.

  • Use String.prototype.split('') and Array.prototype.reduce() to create a hash of the input string, utilizing bit shifting.

Sample Solution:

JavaScript Code:

//#Source https://bit.ly/2neWfJ2 
const sdbm = str => {
  let arr = str.split('');
  return arr.reduce(
    (hashCode, currentVal) =>
      (hashCode = currentVal.charCodeAt(0) + (hashCode << 6) + (hashCode << 16) - hashCode),
    0
  );
};
console.log(sdbm('w3r'));
console.log(sdbm('name'));

Sample Output:

986464758
-3521204949

Flowchart:

flowchart: Hash an given input string into a whole numbers

Live Demo:

See the Pen javascript-basic-exercise-99-1 by w3resource (@w3resource) on CodePen.


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Previous: Write a JavaScript program to filter an array of objects based on a condition while also filtering out unspecified keys.
Next: Write a JavaScript program to create an array of elements, grouped based on the position in the original arrays and using function as the last value to specify how grouped values should be combined.

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JavaScript: Tips of the Day

Chunks an array into n smaller arrays

Example:

const tips_chunkIntoN = (arr, n) => {
  const size = Math.ceil(arr.length / n);
  return Array.from({ length: n }, (v, i) =>
    arr.slice(i * size, i * size + size)
  );
}
console.log(tips_chunkIntoN([1, 2, 3, 4, 5, 6, 7,8], 4)); 

Output:

[[1,2],[3,4],[5,6],[7,8]]