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JavaScript: Hash the input string into a whole number

JavaScript fundamental (ES6 Syntax): Exercise-148 with Solution

Write a JavaScript program to hash 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('name'));

Sample Output:

-3521204949

Flowchart:

flowchart: Hash the input string into a whole number

Live Demo:

See the Pen javascript-basic-exercise-148-1 by w3resource (@w3resource) on CodePen.


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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]]