88. Merge Sorted Array

/*Runtime: 0 ms, faster than 100.00% of Java online submissions for Merge Sorted Array.
Memory Usage: 38.8 MB, less than 96.05% of Java online submissions for Merge Sorted Array.*/

class Solution {
    public void merge(int[] nums1, int m, int[] nums2, int n) {
        
        int[] nums3=new int[m+n-1];
        
         for (int i=0; i<nums3.length; i++) 
            nums3[i] =nums1[i];
        
        if(n==0)
            return;
        int i=0,j=0,k=0;
        
        while(i<m && j<n)
        {
            if(nums3[i]<=nums2[j])
                nums1[k++]= nums3[i++];
            else
                nums1[k++]= nums2[j++];
            
           
        }
        
        
        
        while(i<m)
        {
            nums1[k++]=nums3[i++];
        }
        while(j<n)
        {
            nums1[k++]=nums2[j++];
           
        }
        
    }
}


/*

second approach
Runtime: 0 ms, faster than 100.00% of Java online submissions for Merge Sorted Array.
Memory Usage: 38.9 MB, less than 89.90% of Java online submissions for Merge Sorted Array.*/

class Solution {
    public void merge(int[] nums1, int m, int[] nums2, int n) {
         
        
       int i=m-1, j=n-1, k=m+n-1;
       
        while(i>=0 && j>=0)
        {
            if(nums1[i]>=nums2[j])
            nums1[k--]=nums1[i--];
            else
            nums1[k--]=nums2[j--];    
        }
        
        while(j>=0)
            nums1[k--]=nums2[j--];
            
        
       
        
    }
}