Question

Write a java function to process an array as follows:

1) reverse the contents of an array

2) merge together two arrays

3) merge together two sorted arrays to yield a sorted array

4) append one array onto the end of another

Answer 1

public class Main
{
//method : 1)reverse the contents of an array
   static void reverse(int a[])
   {
   int n =a.length;
   int l=n-1;
   //reversing array
   for(int i=0;i<(n/2);i++)
   {
   int k =a[i];
   a[i]=a[l-i];
   a[l-i]=k;
   }
   }
   //method to 2)merge together two arrays and into new array and returns it
   static int[] merge(int a[],int b[])
   {
   int n = a.length+b.length;
   int c[] = new int[n];
   int i=0;
   for(int j=0;j<a.length;j++)
   c[i++]=a[j];
   for(int j=0;j<b.length;j++)
   c[i++]=b[j];
   return c;
   }
   //method to 3) merge together two sorted arrays to yield a sorted array and returns the sorted arrray
   static int[] mergeSortedArrays(int a[], int b[])
{
int i = 0, j = 0, k = 0;
int n1 = a.length;
int n2=b.length;
int c[] = new int[n1+n2];
// Traverse both array
while (i<n1 && j <n2)
{
if (a[i] <b[j])
c[k++] = a[i++];
else
c[k++] = b[j++];
}
  
while (i < n1)
c[k++] = a[i++];
  
// Store remaining elements of second array
while (j < n2)
c[k++] = b[j++];
return c;
}
//method to 4) append one array onto the end of another
   static void append(int a[],int b[])
   {
   int n = a.length+b.length;
   int c[] = new int[n];
   int i=0;
   for(int j=0;j<a.length;j++)
   c[i++]=a[j];
   for(int j=0;j<b.length;j++)
   c[i++]=b[j];
   a=c;
   }
   public static void main(String[] args) {
      
   }
}