JavaScript: Get all possible subset with a fixed length combinations in an array

JavaScript Function: Exercise-21 with Solution

Fixed-Length Subsets

Write a JavaScript function to get all possible subsets with a fixed length (for example 2) combinations in an array.

Sample array : [1, 2, 3] and subset length is 2

Expected output : [[1,2],[1,3],[2,3]]

Sample Solution:

JavaScript Code:

// Function to get all possible subsets with a fixed length
function getSubsetsWithLength(arr, length) {
    const result = [];

    // Recursive function to generate subsets
    function generateSubsets(currentSubset, start) {
        if (currentSubset.length === length) {
            result.push([...currentSubset]); // Add a copy of the currentSubset to the result
            return;
        }

        for (let i = start; i < arr.length; i++) {
            currentSubset.push(arr[i]);
            generateSubsets(currentSubset, i + 1);
            currentSubset.pop();
        }
    }

    generateSubsets([], 0);
    return result;
}

// Example usage:
const inputArray = [1, 2, 3];
const subsetLength = 2;
const resultSubsets = getSubsetsWithLength(inputArray, subsetLength);

// Log the result to the console
console.log(resultSubsets);

Output:

[[1,2],[1,3],[2,3]]

Flowchart:

Live Demo:

See the Pen JavaScript - Get all possible subset with a fixed length combinations in an array-function-ex- 21 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

• Write a JavaScript function that generates all subsets of an array with a fixed length using a recursive approach.
• Write a JavaScript function that returns all unique combinations of a specified length from an array.
• Write a JavaScript function that generates fixed-length subsets and sorts each subset before adding it to the final result.
• Write a JavaScript function that computes fixed-length subsets from an array without resorting to built-in combinatorics libraries.

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