algorithms16.html

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//https://www.freecodecamp.org/learn/javascript-algorithms-and-data-structures/intermediate-algorithm-scripting/steamroller 
//Flatten a nested array. You must account for varying levels of nesting.


//solution #1
// function steamrollArray(arr) {
//     var newArr =[];
//     for (var i=0; i<arr.length; i++) {
//         if (Array.isArray(arr[i])){
//             //use recursion to flatten the sub-array
//             newArr.push(...steamrollArray(arr[i]));
//         } else {
//             newArr.push(arr[i]);
//         }
//     }
    
//     return newArr;
// }

// solution #2
function steamrollArray(arr){
    return arr.map(e=> {
        if (Array.isArray(e)){
            return steamrollArray(e);
        } else {
            return [e];
        }
    }).reduce((a,b)=>a.concat(b), []);
}

//tests 
console.log(steamrollArray([1, [2], [3, [[4]]]]));
console.log(steamrollArray([[["a"]], [["b"]]]));
console.log(steamrollArray([1, [2], [3, [[4]]]]));
console.log(steamrollArray([[1, [], [3, [[4]]]]]));
console.log(steamrollArray([[1, [], [3, [[4]]]]]));
console.log(steamrollArray([1, {}, [3, [[4]]]]));

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