JavaScript : Hash an given input string into a whole number

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

Hash String into Number

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
// Define the 'sdbm' function to generate a hash code using the SDBM algorithm for a given string.
const sdbm = str => {
  // Convert the string into an array of characters.
  let arr = str.split('');
  // Reduce the array to calculate the hash code using the SDBM algorithm.
  return arr.reduce(
    (hashCode, currentVal) =>
      // Calculate the hash code using the SDBM algorithm.
      (hashCode = currentVal.charCodeAt(0) + (hashCode << 6) + (hashCode << 16) - hashCode),
    0
  );
};

// Test the 'sdbm' function with sample strings.
console.log(sdbm('w3r'));  
console.log(sdbm('name'));

Output:

986464758
-3521204949

Flowchart:

Live Demo:

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

For more Practice: Solve these Related Problems:

• Write a JavaScript program that converts a string into a numeric hash using a simple hash algorithm.
• Write a JavaScript function that iterates over a string’s characters and computes a hash value based on their char codes.
• Write a JavaScript program that generates a whole number hash from an input string while handling collisions minimally.

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