how to merge two sorted array in one sorted array in JavaScript without using sort()

Question

In this program merged two array and then sorted using temp.but this not correct method.because two array are sorted ,so method should be unique i.e. merging of two sorted i

Answer 1

The issue I see with most solutions here is that they don't precreate the array, just pushing into an array when you know the end game size is a little bit wasteful.

This is my suggestion, we can make it a little more efficient but it will make it less readable:

function mergeSortedArrays(arr1, arr2) {
		let i1 = 0, i2 = 0;
		return [...arr1, ...arr2].map(
			() =>
				i1 === arr1.length ? arr2[i2++] :
				i2 === arr2.length ? arr1[i1++] :
				arr1[i1] < arr2[i2]? arr1[i1++] :
				arr2[i2++]
		);
}

console.log(mergeSortedArrays([1,2,3,5,9],[4,6,7,8]))