# 4. Median of Two Sorted Arrays

There are two sorted arrays nums1 and nums2 of size m and n respectively.

Find the median of the two sorted arrays. The overall run time complexity should be O(log (m+n)).

You may assume nums1 and nums2 cannot be both empty.

Example 1:

nums1 = [1, 3]
nums2 = [2]

The median is 2.0
Example 2:

nums1 = [1, 2]
nums2 = [3, 4]

The median is (2 + 3)/2 = 2.5

``````
/**
* @param {number[]} nums1
* @param {number[]} nums2
* @return {number}
*/
var findMedianSortedArrays = function(nums1, nums2) {
// remove elements from both ends

while ((nums1.length + nums2.length)/2 > 1){
// If any of the arrays is empty, rm the other one
if(nums1.length == 0){
nums2.shift();
nums2.pop();
} else if(nums2.length == 0){
nums1.shift();
nums1.pop();
} else {
if(nums1[0] < nums2[0]){
nums1.shift();
} else {
nums2.shift();
}
// if nums1 is empty
//   OR nums1's tail is less than nums2's, remove nums2
if(nums1.length == 0 ||
nums1[nums1.length -1] < nums2[nums2.length -1]){
nums2.pop();
} else {
nums1.pop();
}
}
}
// only 1 or 2 elements remain now
var r = nums1.concat(nums2);
// send average for two
if(r.length > 1){
return (r[0]+r[1])/2;
} else {
// or just the last element
return r[0];
}
};
``````