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S Sarumathi
S Sarumathi

Posted on

Recursion Program

1.Print 1 to N:

Java Script:
Program:

function print(n){
    if(n == 0) return;
    print(n-1);
    console.log(n);
}

print(5);
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Java:
Program:

class Main{
    static void print(int n){
        if(n == 0) return;
        print(n-1);
        System.out.println(n);
    }

    public static void main(String args[]){
        print(5);
    }
}
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Python:
Program:

def print_num(n):
    if n == 0:
        return
    print_num(n-1)
    print(n)

print_num(5)
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2. Fibonacci:

Java Script:
Program:

function fib(n){
    if(n <= 1) return n;
    return fib(n-1) + fib(n-2);
}

console.log(fib(6));
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Java:
Program:

class Main{
    static int fib(int n){
        if(n <= 1) return n;
        return fib(n-1) + fib(n-2);
    }

    public static void main(String args[]){
        System.out.println(fib(6));
    }
}
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Python:
Program:

def fib(n):
    if n <= 1:
        return n
    return fib(n-1) + fib(n-2)

print(fib(6))
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3. Power of Number:

Java Script:
Program:

function power(a,b){
    if(b == 0) return 1;
    return a * power(a,b-1);
}

console.log(power(2,5));
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Java:
Program:

class Main{
    static int power(int a,int b){
        if(b == 0) return 1;
        return a * power(a,b-1);
    }

    public static void main(String args[]){
        System.out.println(power(2,5));
    }
}
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Python:
Program:

def power(a,b):
    if b == 0:
        return 1
    return a * power(a,b-1)

print(power(2,5))
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4. Reverse Number:

Java Script:
Program:

function reverse(n, rev=0){
    if(n == 0) return rev;
    return reverse(Math.floor(n/10), rev*10 + n%10);
}

console.log(reverse(1234));
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Java:
Program:

class Main{
    static int reverse(int n, int rev){
        if(n == 0) return rev;
        return reverse(n/10, rev*10 + n%10);
    }

    public static void main(String args[]){
        System.out.println(reverse(1234,0));
    }
}
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Python:
Program:

def reverse(n, rev=0):
    if n == 0:
        return rev
    return reverse(n//10, rev*10 + n%10)

print(reverse(1234))
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5. Count Digits:

Java Script:
Program:

function count(n){
    if(n == 0) return 0;
    return 1 + count(Math.floor(n/10));
}

console.log(count(12345));

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Java:
Program:

class Main{
    static int count(int n){
        if(n == 0) return 0;
        return 1 + count(n/10);
    }

    public static void main(String args[]){
        System.out.println(count(12345));
    }
}
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Python:
Program:

def count(n):
    if n == 0:
        return 0
    return 1 + count(n//10)

print(count(12345))
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6. Even Numbers:

Java Script:
Program:

function even(n){
    if(n > 10) return;
    console.log(n);
    even(n+2);
}

even(2);
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Java:
Program:

class Main{
    static void even(int n){
        if(n > 10) return;
        System.out.println(n);
        even(n+2);
    }

    public static void main(String args[]){
        even(2);
    }
}
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Python:
Program:

def even(n):
    if n > 10:
        return
    print(n)
    even(n+2)

even(2)
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7. Sum of Digits:

Java Script:
Program:

function sum(n){
    if(n == 0) return 0;
    return n%10 + sum(Math.floor(n/10));
}

console.log(sum(123));
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Java:
Program:

class Main{
    static int sum(int n){
        if(n == 0) return 0;
        return n%10 + sum(n/10);
    }

    public static void main(String args[]){
        System.out.println(sum(123));
    }
}

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Python:
Program:

def sum_digit(n):
    if n == 0:
        return 0
    return n%10 + sum_digit(n//10)

print(sum_digit(123))
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8. Palindrome Number:

Java Script:
Program:

function reverse(n, rev = 0){
    if(n == 0) return rev;
    return reverse(Math.floor(n/10), rev*10 + n%10);
}

let num = 121;

if(num == reverse(num))
    console.log("Palindrome");
else
    console.log("Not Palindrome");
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Java:
Program:

class Main{

    static int reverse(int n, int rev){
        if(n == 0) return rev;
        return reverse(n/10, rev*10 + n%10);
    }

    public static void main(String args[]){

        int num = 121;

        if(num == reverse(num,0))
            System.out.println("Palindrome");
        else
            System.out.println("Not Palindrome");
    }
}
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Python:
Program:

def reverse(n, rev=0):
    if n == 0:
        return rev
    return reverse(n//10, rev*10 + n%10)

num = 121

if num == reverse(num):
    print("Palindrome")
else:
    print("Not Palindrome")
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9. GCD (Greatest Common Divisor):

Java Script:
Program:

function gcd(a,b){
    if(b == 0) return a;
    return gcd(b, a % b);
}

console.log(gcd(12,8));
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Java:
Program:

class Main{

    static int gcd(int a,int b){
        if(b == 0) return a;
        return gcd(b, a%b);
    }

    public static void main(String args[]){
        System.out.println(gcd(12,8));
    }
}
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Python:
Program:

def gcd(a,b):
    if b == 0:
        return a
    return gcd(b, a%b)

print(gcd(12,8))
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10. Print Array Using Recursion:

Java Script:
Program:

function print(arr, index){
    if(index == arr.length) return;

    console.log(arr[index]);
    print(arr, index + 1);
}

let arr = [10,20,30,40,50];
print(arr,0);
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Java:
Program:

class Main{

    static void print(int arr[], int index){

        if(index == arr.length) return;

        System.out.println(arr[index]);
        print(arr, index+1);
    }

    public static void main(String args[]){

        int arr[] = {10,20,30,40,50};
        print(arr,0);
    }
}
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Python:
Program:

def print_arr(arr, index):
    if index == len(arr):
        return

    print(arr[index])
    print_arr(arr, index+1)

arr = [10,20,30,40,50]
print_arr(arr,0)

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Top comments (1)

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payilagam_135383b867ea296 profile image
Payilagam

Could you understand array programs in python?