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# AI solution for JavaScript Coding Question on BFE.dev

81. merge sorted arrays

One possible solution with a time complexity of O(n log n) is:

`function merge(arrays) { let result = []; // Merge each pair of adjacent arrays while (arrays.length > 1) { let merged = []; let a = arrays.shift(); let b = arrays.shift(); let i = 0; let j = 0; while (i < a.length && j < b.length) { if (a[i] <= b[j]) { merged.push(a[i]); i++; } else { merged.push(b[j]); j++; } } while (i < a.length) { merged.push(a[i]); i++; } while (j < b.length) { merged.push(b[j]); j++; } arrays.push(merged); } // Concatenate the remaining arrays result = arrays[0] || []; for (let i = 1; i < arrays.length; i++) { result = result.concat(arrays[i]); } return result;}`

The solution uses a loop to repeatedly merge pairs of adjacent arrays into a single larger array until there is only one array remaining. This takes O(log n) iterations, where n is the number of input arrays.

Inside each iteration, we perform a merge of two arrays, which takes O(n) time, where n is the total number of elements in the two arrays.

Finally, we concatenate the remaining arrays, which takes O(n) time, where n is the total number of remaining elements.

Overall, the time complexity of this solution is O(n log n).