Implement myFlatMap (Array.prototype.flatMap)

Created byeLearn Core Team

Implement `myFlatMap(arr, callback)`

Write myFlatMap(arr, callback): map every element through callback, then flatten the result exactly one level deep, no more, regardless of how deeply nested the mapped values are.

myFlatMap([1, 2, 3], (n) => [n, n * 2]);   // [1, 2, 2, 4, 3, 6]
myFlatMap([[1, 2], [3]], (a) => [a]);       // [[1, 2], [3]] (only one level undone)

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Implement myFlatMap (Array.prototype.flatMap)

Implement myFlatMap(arr, callback)

Unlock All 130+ Coding Challenges

Implement myFlatMap (Array.prototype.flatMap)

Implement myFlatMap(arr, callback)

Unlock All 130+ Coding Challenges

Implement `myFlatMap(arr, callback)`

Implement `myFlatMap(arr, callback)`