Question

Write a flatten function in JavaScript that uses recursion to create an array containing all nested arrays in a single array. The function should pass the test:

 it("longer list, no mutation, completely flat",
        function () {
            var data = [[[1],2,[3]],4,[5,6]];
            var orig_data = data;
            expect(ms.flatten(data)).toEqual([1,2,3,4,5,6]);
            expect(data).toEqual(orig_data);
        });

Answer 1

function flatten(array){

let arr=[];

function helper(array){

for(let i = 0;i<array.length;i++){

let element=array[i];

if(Array.isArray(element)){

arr=arr.concat(flatten(element));

    }

    else{

        arr.push(element);

    }

   }

}

helper(array);

return arr;

}

console.log(flatten([[[1],2,[3]],4,[5,6]]));

this the function of flatten you can use this function in your file

If you found this answer helpful please give a thumbs