88.merge-sorted-array.java

/*
 * @lc app=leetcode id=88 lang=java
 *
 * [88] Merge Sorted Array
 *
 * https://leetcode.com/problems/merge-sorted-array/description/
 *
 * algorithms
 * Easy (34.87%)
 * Total Accepted:    348K
 * Total Submissions: 985.6K
 * Testcase Example:  '[1,2,3,0,0,0]\n3\n[2,5,6]\n3'
 *
 * 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]
 *
 *
 */
class Solution {
  public void merge(int[] nums1, int m, int[] nums2, int n) {
    int i = m - 1;
    int j = n - 1;
    int k = m + n - 1;

    while (i >= 0 && j >= 0) {
      nums1[k--] = (nums1[i] > nums2[j]) ? nums1[i--] : nums2[j--];
    }

    while (j >= 0) {
      nums1[k--] = nums2[j--];
    }
  }
}