JavaScript: Generate an array between two integers of 1 step length

JavaScript Array: Exercise-41 with Solution

Array Between Two Integers

Write a JavaScript function to generate an array between two integers of 1 step length.

Test Data :
console.log(rangeBetwee(4, 7));
[4, 5, 6, 7]
console.log(rangeBetwee(-4, 7));
[-4, -3, -2, -1, 0, 1, 2, 3, 4, 5, 6, 7]

Visual Presentation:

Sample Solution:

JavaScript Code:

// Function to generate an array of numbers between two values (inclusive)
function rangeBetween(start, end) 
{
  if (start > end) {
    // If start is greater than end, create a new array and fill it in reverse order
    const arr = Array.from({ length: start - end + 1 }, (_, index) => start - index);
    return arr;
  } else {
    // If start is less than or equal to end, create a new array and fill it in ascending order
    const arr = Array.from({ length: end - start + 1 }, (_, index) => start + index);
    return arr;
  }
}

// Output the result of generating an array between 4 and 7 (inclusive)
console.log(rangeBetween(4, 7));

// Output the result of generating an array between -4 and 7 (inclusive)
console.log(rangeBetween(-4, 7));

Output:

[4,5,6,7]
[-4,-3,-2,-1,0,1,2,3,4,5,6,7]

Flowchart:

ES6 Version:

// Function to generate an array of numbers between two values (inclusive)
function rangeBetween(start, end) {
  // Use conditional (ternary) operator to determine the direction of filling the array
  const arr = start > end
    ? Array.from({ length: start - end + 1 }, (_, index) => start - index)
    : Array.from({ length: end - start + 1 }, (_, index) => start + index);

  // Return the generated array
  return arr;
}

// Output the result of generating an array between 4 and 7 (inclusive)
console.log(rangeBetween(4, 7));

// Output the result of generating an array between -4 and 7 (inclusive)
console.log(rangeBetween(-4, 7));

Live Demo :

See the Pen JavaScript -Generate an array between two integers of 1 step length-array-ex- 41 by w3resource (@w3resource) on CodePen.

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