Question

1. Write a recursive function that computes the sum of all numbers from 1 to n, where n is given as parameter.

Here is the method header: public static int sum (int n){...}

2. Write a recursive function that finds and returns the minimum value in an array, where the array and its size are given as parameters.

Here is the method header: public static int minValue (int [] data, int size){...}

3. Write a recursive function that reverses the elements in an array, where the array, indices of the first and the last value in the array are given as parameters.

Here is the method header: public static void reverse (int [] data, int start, int end){...}

Answer 1

import java.util.*;
class RecurSum
{
public static int sum(int n)
{
if(n==0)
return 0;
else
return n+sum(n-1);
}
public static void main(String args[])
{
Scanner sc=new Scanner(System.in);
System.out.println("Enter n Value");
int n=sc.nextInt();
System.out.println("The Sum if First "+n+" Numbers is

"+sum(n));
}
}

XUsers sagarjavac RecurSun.jaua Users sagarja Recur Sun ter n Ualue he Sun if First 15 Numbcrs is 120

import java.util.*;
class FindMin
{
private static int findMin(int[] data, int index) {
if(index==0)
return data[0];
if(data[index-1] < findMin(data , index -1))
return data[index -1];
else
return (findMin(data , index -1));

}
public static void main(String args[])
{
Scanner sc=new Scanner(System.in);
System.out.println("Enter How Many Elements");
int n=sc.nextInt();
int a[]=new int[n];
for(int i=0;i<n;i++)
{
System.out.println("Enter "+(i+1)+" Element");
a[i]=sc.nextInt();
}
System.out.println("The Minimum Element is "+findMin

(a,n));
}
}

S. CAWin CUsersagajavac FindMin-java Users sagariava FindMin Enter How Many Elements Enter 1 Element Enter 2 Element Enter 3 Element Enter 4 Element Enter 5 Element Enter 6 Element The Minimum Element is -8 C Uses sagar> RSHIPS Search ay, where the array rray, indices of the SUBMIT ANSWER 10:55 AM 5/19/2017

import java.util.*;
class ReverseArray
{
public static void reverse(int[] data,int start,int end)
{
int temp;
if (start >= end)
return;
temp = data[start];
data[start] = data[end];
data[end] = temp;
reverse(data, start+1, end-1);
}
static void print(int[] data,int size)
{
int i;
for (i=0; i < size; i++)
System.out.print(data[i] + " ");
System.out.println("");
}
public static void main (String[] args) {
Scanner sc=new Scanner(System.in);
System.out.println("Enter How Many Elements");
int n=sc.nextInt();
int data[] = new int[n];
for(int i=0;i<n;i++)
{
System.out.println("Enter "+(i+1)+" Element");
data[i]=sc.nextInt();
}
print(data, n);
reverse(data, 0, n-1);
System.out.println("Reversed array is ");
print(data, n);
}
}

S. CAWin CNUsersagajavac ReverseArray.java Users sagarjava ReverseArray Enter How Many Elements Enter 1 Element Enter 2 Element Enter 3 Element Enter 4 Element Enter 5 Element Enter 6 Element RSHIPS Search ay, where the array rray, indices of the Reversed arvay is 8 96 5 2 3 SUBMIT ANSWER 11:07 AM 5/19/2017