You are given two integer arrays nums1 and nums2, sorted in non-decreasing order, and two integers m and n, representing the number of elements in nums1 and nums2 respectively.

Merge nums1 and nums2 into a single array sorted in non-decreasing order.

The final sorted array should not be returned by the function, but instead be stored inside the array nums1. To accommodate this, nums1 has a length of m + n, where the first m elements denote the elements that should be merged, and the last n elements are set to 0 and should be ignored. nums2 has a length of n.

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Example 1:

Input: nums1 = [1,2,3,0,0,0], m = 3, nums2 = [2,5,6], n = 3
Output: [1,2,2,3,5,6]
Explanation: The arrays we are merging are [1,2,3] and [2,5,6].
The result of the merge is [1,2,2,3,5,6] with the underlined elements coming from nums1.


Example 2:

Input: nums1 = [1], m = 1, nums2 = [], n = 0
Output: [1]
Explanation: The arrays we are merging are [1] and [].
The result of the merge is [1].


Example 3:

Input: nums1 = [0], m = 0, nums2 = [1], n = 1
Output: [1]
Explanation: The arrays we are merging are [] and [1].
The result of the merge is [1].
Note that because m = 0, there are no elements in nums1. The 0 is only there to ensure the merge result can fit in nums1.


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Constraints:


	nums1.length == m + n
	nums2.length == n
	0 &lt;= m, n &lt;= 200
	1 &lt;= m + n &lt;= 200
	-109 &lt;= nums1[i], nums2[j] &lt;= 109


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Follow up: Can you come up with an algorithm that runs in O(m + n) time?

class Solution(object):
    def merge(self, nums1, m, nums2, n):
        # Initialize nums1's index
        i = m - 1
        # Initialize nums2's index
        j = n - 1
        # Initialize a variable k to store the last index of the 1st array...
        k = m + n - 1
        while j >= 0:
            if i >= 0 and nums1[i] > nums2[j]:
                nums1[k] = nums1[i]
                k -= 1
                i -= 1
            else:
                nums1[k] = nums2[j]
                k -= 1
                j -= 1
class Solution {
    public void merge(int[] nums1, int m, int[] nums2, int n) {
        // Initialize i and j to store indices of the last element of 1st and 2nd array respectively...
        int i = m - 1 , j = n - 1;
        // Initialize a variable k to store the last index of the 1st array...
        int k = m + n - 1;
        // Create a loop until either of i or j becomes zero...
        while(i >= 0 && j >= 0) {
            if(nums1[i] >= nums2[j]) {
                nums1[k] = nums1[i];
                i--;
            } else {
                nums1[k] = nums2[j];
                j--;
            }
            k--;
        // Either of i or j is not zero, which means some elements are yet to be merged.
        // Being already in a sorted manner, append them to the 1st array in the front.
        }
        // While i does not become zero...
        while(i >= 0)
            nums1[k--] = nums1[i--];
        // While j does not become zero...
        while(j >= 0)
            nums1[k--] = nums2[j--];
        // Now 1st array has all the elements in the required sorted order...
        return;
    }
}
class Solution {
public:
    void merge(vector<int>& nums1, int m, vector<int>& nums2, int n) {
        vector<int> temp(n+m);
        int i=0,j=0,k=0;
        while(i<m && j<n){ //select smaller element from both vector
            if(nums1[i]<nums2[j]){
                temp[k]=nums1[i];
                i++;
                k++;
            }
            else{
                temp[k]=nums2[j];
                j++;
                k++;
            }
        }
        while(i<m){ //insert remaining nums1 element
            temp[k]=nums1[i];
            i++;
            k++;
        }
        while(j<n){ //insert remaining nums2 element
            temp[k]=nums2[j];
            j++;
            k++;
        }
        nums1=temp;
        return ;
    }
};
var merge = function(nums1, m, nums2, n) {
    // Initialize i and j to store indices of the last element of 1st and 2nd array respectively...
    let i = m - 1 , j = n - 1;
    // Initialize a variable k to store the last index of the 1st array...
    let k = m + n - 1;
    // Create a loop until either of i or j becomes zero...
    while(i >= 0 && j >= 0) {
        if(nums1[i] >= nums2[j]) {
            nums1[k] = nums1[i];
            i--;
        } else {
            nums1[k] = nums2[j];
            j--;
        }
        k--;
    // Either of i or j is not zero, which means some elements are yet to be merged.
    // Being already in a sorted manner, append them to the 1st array in the front.
    }
    // While i does not become zero...
    while(i >= 0)
        nums1[k--] = nums1[i--];
    // While j does not become zero...
    while(j >= 0)
        nums1[k--] = nums2[j--];
    // Now 1st array has all the elements in the required sorted order...
    return;
};
Merge Sorted Array