[leetcode]88. Merge Sorted Array

Given two sorted integer arrays nums1 and nums2, merge nums2 into nums1 as one sorted array.

Note:

The number of elements initialized in nums1 and nums2 are m and n respectively.
You may assume that nums1 has enough space (size that is greater or equal to m + n) to hold additional elements from nums2.
Example:

Input:
nums1 = [1,2,3,0,0,0], m = 3
nums2 = [2,5,6], n = 3

Output: [1,2,2,3,5,6]

var merge = function (a, m, b, n) {
            var i = 0, j = 0, k = 0
            var c = [];
            var k = 0
            

            //n, m分别为a,b的最后索引; i为a的索引，j为b的索引，k为c的索引
            var u = 0;
            while (i < m && j < n) {
                c[k++] = a[i] < b[j] ? a[i++] : b[j++];
               
            }
            var u = 0
            while (i < m) {
                c.push(a[i++])
                
            }
            var u = 0
            while (j < n) {
                c.push(b[j++])
               
            }
            i = 0
            var mn = m + n;
            a.length = mn;
            while (i < mn) {
                a[i] = c[i];
                i++
               
            }
            console.log(a)
        };

        merge([1, 2, 3, 0, 0, 0], 3, [2, 5, 6], 3)
        merge([1], 1, [], 0)

       merge( [2,0],1,[1],1)