Print numbers from 1 to n using recursion
Recursion is a programming technique where a function calls itself to solve a smaller subproblem until a base case is reached. In this article, we will explore how to print numbers from 1 to N using recursion in Java.
Problem Statement
Given a positive integer N, we need to print all the numbers from 1 to N using recursion.
Example
Let's take N = 5 as an example. The expected output should be: 1 2 3 4 5
Similarly
Example N = 10
(1 to 10) : 1 2 3 4 5 6 7 8 9 10
Example N = 20
(1 to 20) : 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20
Pseudocode
The recursive approach to print numbers from 1 to N can be represented using the following pseudocode:
function printNumber(num)
if num is greater than or equal to 1
Call printNumber(num  1) // Recursive call with a smaller problem
Print num // Display the current number
Algorithm Explanation
 The
printNumber
function takes an integernum
as its argument.  It checks if
num
is greater than or equal to 1, which is the base case for recursion.  If the base case is not reached, it calls the
printNumber
function recursively withnum  1
.  The recursive call ensures that the numbers are printed in ascending order from 1 to
num
.  After the recursive call, the current value of
num
is printed on the console.
Programming Solution
Recursion is a technique in programming where a function calls itself repeatedly until a specific condition is met. In this case, the function would call itself with decreasing values of n until it reaches 1, printing each value as it goes.

1) Print numbers from 1 to n using recursion in java
2) Print numbers from 1 to n using recursion in c++
3) Print numbers from 1 to n using recursion in c
4) Print numbers from 1 to n using recursion in c#
5) Print numbers from 1 to n using recursion in vb.net
6) Print numbers from 1 to n using recursion in php
7) Print numbers from 1 to n using recursion in node js
8) Print numbers from 1 to n using recursion in typescript
9) Print numbers from 1 to n using recursion in python
10) Print numbers from 1 to n using recursion in ruby
11) Print numbers from 1 to n using recursion in scala
12) Print numbers from 1 to n using recursion in swift
13) Print numbers from 1 to n using recursion in kotlin
14) Print numbers from 1 to n using recursion in golang
Resultant Output Explanation
The code provided in the example prints the numbers from 1 to N (10 and 20 in this case) using the
printNumber
function. The main
function initializes an instance of the
Numbers
class and calls the printNumber
function with different values of
num
.
For num = 10
, the output is "1 2 3 4 5 6 7 8 9 10". This output demonstrates that the recursive function
is working correctly and printing the numbers in the expected order.
For num = 20
, the output is "1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20". Similarly, this output
confirms that the function can handle larger values of num
and still print the numbers from 1 to
num
correctly.
Time Complexity
The time complexity of this recursive approach to print numbers from 1 to N is O(N). The function makes N recursive calls, and each call performs constant time operations (printing the number). As a result, the time complexity is linear with respect to N.
Please share your knowledge to improve code and content standard. Also submit your doubts, and test case. We improve by your feedback. We will try to resolve your query as soon as possible.
New Comment