Question

In java

1. Write a recursive algorithm to add all the elements of an array of n elements

2. Write a recursive algorithm to get the minimum element of an array of n elements

3. Write a recursive algorithm to add the corresponding elements of two arrays (A and B) of n elements. Store the results in a third array C.

4. Write a recursive algorithm to get the maximum element of a binary tree

5. Write a recursive algorithm to get the number of elements of a binary tree

Answer 1

1. Write a recursive algorithm to add all the elements of an array of n elements

static int Cal_Sum(int arr[], int n) 
{ 
    if (n <= 0)     // base condition
        return 0; 
    return (Cal_Sum(arr, n - 1)+arr[n - 1]);   // recursive call
}

2. Write a recursive algorithm to get the minimum element of an array of n elements

public static int find_MAX(int arr[], int n) 
{ 
    if(n == 1) // base condition 
    return arr[0];  
    return Math.max(arr[n-1], find_MAX(arr, n-1));   //recursive call
} 

3. Write a recursive algorithm to add the corresponding elements of two arrays (A and B) of n elements. Store the results in a third array C.

static int[] fun(int a[], int b[],int c[],int n)
{
    if(n==0)    //base condition
    return c;
    c[n-1]=a[n-1]+b[n-1];   //add sum to c array 
    return fun(a,b,c,n-1);   //recursive call
}

4. Write a recursive algorithm to get the maximum element of a binary tree

static int MAX_ELEMENT(Node node) 
{ 
    if (node == null)             // base condition
        return Integer.MIN_VALUE; 
    int ans = node.data; 
    int left_ans = MAX_ELEMENT(node.left);   //recursive call
    int right_ans = MAX_ELEMENT(node.right); //recursive call
    if (right_ans > ans)         // finding max
        ans = right_ans;
    if (left_ans > ans)          // finding max
        ans = left_ans; 
    
    return ans; 
} 

5. Write a recursive algorithm to get the number of elements of a binary tree

static int Count_Nodes(Node root)
{
    if(root==null)  //  base condition
        return 0;
    return (1 + Count_Nodes(root.left) + Count_Nodes(root.right));  //recursive call
}

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