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Ruby program to find the given number is PRIME or not using recursion

Ruby Example: Write a program to find the given number is PRIME or not using recursion.
Submitted by Nidhi, on December 25, 2021

Problem Solution:

In this program, we will read an integer number from the user and find the input number is PRIME or not using recursion.

Program/Source Code:

The source code to find the given number is PRIME or not using recursion is given below. The given program is compiled and executed successfully.

# Ruby program to find the given number 
# is PRIME or not using recursion

def checkPrime(num, i)
    if (i == 1)
        return 1;
    else
       if (num % i == 0)
         return 0;
       else
         return checkPrime(num, i - 1);
       end    
    end
end

print "Enter number: ";
number = gets.chomp.to_i;  

result = checkPrime(number, number/2);

if result==1
    print "Given number is PRIME number.";
else
    print "Given number is not PRIME number.";
end

Output:

Enter number: 11
Given number is PRIME number.

Explanation:

In the above program, we read an integer number from the user. Then we found the input number is PRIME or not using recursive function checkPrime(). Then we printed the result.