How to use Reduce method with the Set In Javascript
In this approach, we are using the reduce method to and the forEach method to iterate over all the input arrays, and all this is stored in the set, where the unqualified values are considered. Later, we will convert this set into an array and print the result.
Syntax:
return Array.prototype.reduce.call(arguments, function (res, currentArr) {
// Iterate through the current array
}, new Set());
Example: This example shows the use of the above-explained approach.
function mergeUsingReduce() {
// Reduce method will merge the
// multiple input arrays in single set here.
return Array.prototype.reduce.call(
arguments,
function (res, currentArr) {
// Iterate over each element
// in the currentArray.
currentArr.forEach(
function (ele) {
res.add(ele);
}
);
return res;
},
new Set()
);
}
// Multiple input arrys. You can increase
// and pass to the function
let inputArray1 = [1, 2, 3, 4, 5];
let inputArray2 = [4, 5, 6, 7, 8];
let inputArray3 = [7, 8, 9, 10, 11];
let tempresult = mergeUsingReduce(
inputArray1,
inputArray2,
inputArray3
);
// We are converting Set to the array
// and printing it.
let outputArray =
Array.from(tempresult);
console.log(outputArray);
Output
[ 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11 ]
JavaScript Program to Create an Array of Unique Values From Multiple Arrays Using Set Object
We have given multiple arrays consisting of numerical values, and our task is to create an output array that consists of unique values from the multiple input arrays. We will use the Set object in JavaScript language.
Example:
Input: inputarray1: [1,2,3,4,5] inputarray2: [4,5,6,7,8] Output: outputArray: [1,2,3,4,5,6,7,8]
Table of Content
- Using Set and Spread Operator
- Using the Concat method and Set
- Using Reduce method with the Set
- Using Set Object with flatMap
- Using Set Object with Array.prototype.flat()